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digitalmars.D.announce - Re: dmd 2.029 release

reply bearophile <bearophileHUGS lycos.com> writes:
This post is mostly for Andrei.
I have played with D2 a bit; probably I'll need months to digest it and its new
Phobos2. While I explore Phobos I'll probably post some comments/bugs around
here.

After reading this:
http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features-in-vc10-part-3.aspx
I have tried to write a toy implementation of it in D2 (not using Phobos2 yet):

import std.stdio: writeln;
import std.string: format;

struct Watts {
    int _x;
    int x() const { return this._x; }
    Joules opMul(Seconds s) {
        return Joules(this._x * s.x);
    }
    string toString() { return format("Watts(%s)", this._x); }
}

struct Seconds {
    int _x;
    int x() const { return this._x; }
    Joules opMul(Watts w) {
        return Joules(this._x * w.x);
    }
    string toString() { return format("Seconds(%s)", this._x); }
}

struct Joules {
    int _x;
    int x() const { return this._x; }
    string toString() { return format("Joules(%s)", this._x); }
}

auto map(alias f, TySeq1, TySeq2)(TySeq1 a1, TySeq2 a2) {
    assert(a1.length == a2.length);
    auto result = new typeof( f(a1[0], a2[0]) )[a1.length];
    for (int i; i < a1.length; i++)
        result[i] = f(a1[i], a2[i]);
    return result;
}

void main() {
    auto watts = [Watts(2), Watts(3), Watts(4)];
    writeln(watts);

    auto secs = [Seconds(5), Seconds(6), Seconds(7)];
    writeln(secs);

    auto result = map!( (x, y){ return x*y; } )(watts, secs);
    writeln(result);
}

Few notes:
- Lacking struct inheritance I have duplicated code.
- This whole proggy is not difficult to write. It's simpler than the C++ one.
But I think it's a bit less general.
- Here I have not used const in input arguments yet, nor the map of Phobos2.
- (x, y){ return x*y; } is one of the new template literals. Can I define it
elsewhere, like in an alias? So far I have failed doing that.

Two things to improve:
1) All structs must have a default built-in opString, a good representation can
be:
StructName(field_value1, field_value2, field_value1, ...).
It's not a perfect textual representation, but it's WAY better than the current
one (currently it shows just the struct name).
(Printing the module name before the struct name is bad, most times is just
noise)

2) The output of that program is:
Watts(2) Watts(3) Watts(4)
Seconds(5) Seconds(6) Seconds(7)
Joules(10) Joules(18) Joules(28)

I think a much better output is:
[Watts(2), Watts(3), Watts(4)]
[Seconds(5),  Seconds(6),  Seconds(7)]
[Joules(10),  Joules(18),  Joules(28)]

Note the space after the comma, it's a small detail but it improves readability
significantly.
(This representation doesn't tell apart dynamic arrays from static ones, but I
can live with this).

----------------

I don't remember if vector ops support user-defined opMul too, I have tried
this code, but maybe I am doing something wrong:

...
    Joules[3] result2;
    result2[] = watts[] * secs[];
    writeln(result2);
}

Bye,
bearophile
Apr 23 2009
parent reply Don <nospam nospam.com> writes:
bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it and its
new Phobos2. While I explore Phobos I'll probably post some comments/bugs
around here.
 
 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features-in-vc10-part-3.aspx
 I have tried to write a toy implementation of it in D2 (not using Phobos2 yet):
 
 import std.stdio: writeln;
 import std.string: format;
 
 struct Watts {
     int _x;
     int x() const { return this._x; }
     Joules opMul(Seconds s) {
         return Joules(this._x * s.x);
     }
     string toString() { return format("Watts(%s)", this._x); }
 }
 
 struct Seconds {
     int _x;
     int x() const { return this._x; }
     Joules opMul(Watts w) {
         return Joules(this._x * w.x);
     }
     string toString() { return format("Seconds(%s)", this._x); }
 }
 
 struct Joules {
     int _x;
     int x() const { return this._x; }
     string toString() { return format("Joules(%s)", this._x); }
 }
 
 auto map(alias f, TySeq1, TySeq2)(TySeq1 a1, TySeq2 a2) {
     assert(a1.length == a2.length);
     auto result = new typeof( f(a1[0], a2[0]) )[a1.length];
     for (int i; i < a1.length; i++)
         result[i] = f(a1[i], a2[i]);
     return result;
 }
 
 void main() {
     auto watts = [Watts(2), Watts(3), Watts(4)];
     writeln(watts);
 
     auto secs = [Seconds(5), Seconds(6), Seconds(7)];
     writeln(secs);
 
     auto result = map!( (x, y){ return x*y; } )(watts, secs);
     writeln(result);
 }
 
 Few notes:
 - Lacking struct inheritance I have duplicated code.
 - This whole proggy is not difficult to write. It's simpler than the C++ one.
But I think it's a bit less general.
 - Here I have not used const in input arguments yet, nor the map of Phobos2.
 - (x, y){ return x*y; } is one of the new template literals. Can I define it
elsewhere, like in an alias? So far I have failed doing that.
 
 Two things to improve:
 1) All structs must have a default built-in opString, a good representation
can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than the
current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times is just
noise)



No!
<rant>
toString() is one of the most dreadful features in D. Trying to slightly 
improve it is a waste of time -- the whole concept needs to be redone.
It's horribly inflexible, tedious, and hugely inefficient. What more 
could there be to hate?

- the object being called has no context. It doesn't know what format is 
desired, for example.
- you can't emulate formatting of built-in types, NOT EVEN int! You 
can't do left-align, pad with zeros, include + sign, display in hex.

- it's got no stream concept. Every object has to create and manage its 
own buffer, and nobody knows if anyone actually needs it.

It ought to be at least as simple as:

struct Foo(A, B, C){
A[10] a;
B b;
C c;
void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
}
}
... but it's not, you have to create a silly buffer to put all your 
strings in, even if there are 200 million of them and your giant string 
is just going to be written to a file anyway.

I'd like to see version(debug) {} put around Object.toString(). It's a 
deathtrap feature that's got no business being used other than for 
debugging.
</rant>



 
 2) The output of that program is:
 Watts(2) Watts(3) Watts(4)
 Seconds(5) Seconds(6) Seconds(7)
 Joules(10) Joules(18) Joules(28)
 
 I think a much better output is:
 [Watts(2), Watts(3), Watts(4)]
 [Seconds(5),  Seconds(6),  Seconds(7)]
 [Joules(10),  Joules(18),  Joules(28)]
 
 Note the space after the comma, it's a small detail but it improves
readability significantly.
 (This representation doesn't tell apart dynamic arrays from static ones, but I
can live with this).
 
 ----------------
 
 I don't remember if vector ops support user-defined opMul too, I have tried
this code, but maybe I am doing something wrong:
 
 ...
     Joules[3] result2;
     result2[] = watts[] * secs[];
     writeln(result2);
 }
 
 Bye,
 bearophile
Apr 23 2009
next sibling parent grauzone <none example.net> writes:
 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to slightly 
 improve it is a waste of time -- the whole concept needs to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?



Hey, it's only meant for debugging! (At least I hope.)
Apr 23 2009
prev sibling next sibling parent "Simen Kjaeraas" <simen.kjaras gmail.com> writes:
Don wrote:


 I'd like to see version(debug) {} put around Object.toString(). It's a  
 deathtrap feature that's got no business being used other than for  
 debugging.



That actually sounds like a good idea. Like you say, is has no use
outside of debugging, but while debugging, it's quite useful.

--
  Simen
Apr 23 2009
prev sibling next sibling parent reply "Denis Koroskin" <2korden gmail.com> writes:
On Thu, 23 Apr 2009 16:20:03 +0400, Don <nospam nospam.com> wrote:


 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it and  
 its new Phobos2. While I explore Phobos I'll probably post some  
 comments/bugs around here.
  After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features-in-vc10-part-3.aspx
 I have tried to write a toy implementation of it in D2 (not using  
 Phobos2 yet):
  import std.stdio: writeln;
 import std.string: format;
  struct Watts {
     int _x;
     int x() const { return this._x; }
     Joules opMul(Seconds s) {
         return Joules(this._x * s.x);
     }
     string toString() { return format("Watts(%s)", this._x); }
 }
  struct Seconds {
     int _x;
     int x() const { return this._x; }
     Joules opMul(Watts w) {
         return Joules(this._x * w.x);
     }
     string toString() { return format("Seconds(%s)", this._x); }
 }
  struct Joules {
     int _x;
     int x() const { return this._x; }
     string toString() { return format("Joules(%s)", this._x); }
 }
  auto map(alias f, TySeq1, TySeq2)(TySeq1 a1, TySeq2 a2) {
     assert(a1.length == a2.length);
     auto result = new typeof( f(a1[0], a2[0]) )[a1.length];
     for (int i; i < a1.length; i++)
         result[i] = f(a1[i], a2[i]);
     return result;
 }
  void main() {
     auto watts = [Watts(2), Watts(3), Watts(4)];
     writeln(watts);
      auto secs = [Seconds(5), Seconds(6), Seconds(7)];
     writeln(secs);
      auto result = map!( (x, y){ return x*y; } )(watts, secs);
     writeln(result);
 }
  Few notes:
 - Lacking struct inheritance I have duplicated code.
 - This whole proggy is not difficult to write. It's simpler than the  
 C++ one. But I think it's a bit less general.
 - Here I have not used const in input arguments yet, nor the map of  
 Phobos2.
 - (x, y){ return x*y; } is one of the new template literals. Can I  
 define it elsewhere, like in an alias? So far I have failed doing that.
  Two things to improve:
 1) All structs must have a default built-in opString, a good  
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than the  
 current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times is  
 just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to slightly  
 improve it is a waste of time -- the whole concept needs to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more  
 could there be to hate?

 - the object being called has no context. It doesn't know what format is  
 desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You  
 can't do left-align, pad with zeros, include + sign, display in hex.

 - it's got no stream concept. Every object has to create and manage its  
 own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
     foreach(x; a) sink(x);
     sink(b);
     sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your  
 strings in, even if there are 200 million of them and your giant string  
 is just going to be written to a file anyway.



Absolutely agree, but Sink is not good, either. I have previously suggested the
following design (but can't find my post anymore):

A signature of toString() should be as follows:

char[] toString(string format = null, char[] buffer = null);

Bonuses you get from that:
You don't have to change your code (aside from toString() returning mutable
array now, but it is very easy to fix)
It allows you to avoid allocations - just pass a temporary buffer to use!
It allows you to use advanced formatting options

Example:

class Number {
    private int _number;
    char[] toString(string format = null, char[] buffer = null) {
        Format format = Format.Decimal;        
        switch (format) {
            case "x": format = Format.Hexademical;
            case "X": format = Format.HexademicalUpperCase;
            case "b": format = Format.Binary;
            // ...
        }

        return formatInteger(_number, format, buffer);
    }

    static char[] formatInteger(int value, Format format, char[] buffer)
    {
        // writes to buffer, resizing it
    }
}

Cons: printf-style formatting works badly with this desing.
I belive it should be dropped anyway, in favor of a more flexible .NET-style
formatting:

writefln("My name is {} and I'm 0x{X} years old", Denis, 22);

// calls name.toString("", buffer) and age.toString("X", buffer)
Result: My name is Denis and I'm 0x16 years old.

Here is another example:

MyArray myArray = new MyArray(10, 20, 30);

char[1024] buffer;
string.format(buffer, "Array contents: [{{X}, }]", myArray);

// calls myArray.toString("{X}, ", buffer); which in turn calls
element.toString("X", buffer) on its elements and uses ", " as a separator:
Result: Array contents: [A, 14, 1E]

No allocation involved!
Apr 23 2009
parent reply Frits van Bommel <fvbommel REMwOVExCAPSs.nl> writes:
Denis Koroskin wrote:

 On Thu, 23 Apr 2009 16:20:03 +0400, Don <nospam nospam.com> wrote:
 

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
     foreach(x; a) sink(x);
     sink(b);
     sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your  
 strings in, even if there are 200 million of them and your giant string  
 is just going to be written to a file anyway.



 Absolutely agree, but Sink is not good, either. I have previously suggested
the following design (but can't find my post anymore):
 
 A signature of toString() should be as follows:
 
 char[] toString(string format = null, char[] buffer = null);
 
 Bonuses you get from that:
 You don't have to change your code (aside from toString() returning mutable
array now, but it is very easy to fix)
 It allows you to avoid allocations - just pass a temporary buffer to use!



It'll still allocate if the buffer isn't big enough.

I usually define something like "void streamTo(Sink sink)" in a base class if I 
want non-allocating output. Adding a format string to the parameter list should 
be easy, but I haven't needed it yet.
I then usually implement toString by passing an appending Sink to that method, 
just so Tango's formatting methods will be able to use it.



IMHO It'd be pretty nice for the standard formatting systems (both the Tango
and 
Phobos ones) to just call a standard Object method taking (Sink sink, char[] 
format = null) on objects.

Backward compatibility might be tricky though, if you want to support both 
overriding and calling of toString(). (You can't have the default toString 
implementation call the format function *and* have the default format function 
implementation call toString)

Though I suppose you could take a delegate to toString in the default format 
method and see if the function pointer in it points to Object.toString, just 
calling sink(this.classinfo.name) if so (to emulate current behavior), and 
calling toString() if not...
(Or maybe the other way around; have Object.toString check if the format 
function was overridden, call it if so and return the classname if not)
Apr 23 2009
next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Frits van Bommel wrote:

 I usually define something like "void streamTo(Sink sink)" in a base 
 class if I want non-allocating output. Adding a format string to the 
 parameter list should be easy, but I haven't needed it yet.
 I then usually implement toString by passing an appending Sink to that 
 method, just so Tango's formatting methods will be able to use it.



Yah. The way std.format does it is by operating on an abstract output 
range, and then have Appender!(T[]) implement the output range 
interface. So getting stringizing is as easy as passing an 
Appender!string in there.


 IMHO It'd be pretty nice for the standard formatting systems (both the 
 Tango and Phobos ones) to just call a standard Object method taking 
 (Sink sink, char[] format = null) on objects.



Probably we'll need that. You forgot the "in" though :o).


Andrei
Apr 23 2009
parent Frits van Bommel <fvbommel REMwOVExCAPSs.nl> writes:
Andrei Alexandrescu wrote:

 Frits van Bommel wrote:

 IMHO It'd be pretty nice for the standard formatting systems (both the 
 Tango and Phobos ones) to just call a standard Object method taking 
 (Sink sink, char[] format = null) on objects.



 Probably we'll need that. You forgot the "in" though :o).



That's just because I'm thinking in D1, where it's optional :).
Apr 23 2009
prev sibling next sibling parent grauzone <none example.net> writes:
 Sink is okay, but most my usages belong to one of the two scenarios:
 1) I need a string representation of an Object - how is Sink useful here? I
just want to call obj.toString() and get the result
 2) I need to print it to stdout, thus I call writeln/Stdout(obj); - Sink is of
no use here again.



Needs simple converter code, that safe you from typing trivial stuff 
like this:

toString((char[] s) { writeln(s); });


     void toString(Sink sink, string format = null) {
         // what should I do here? How do I avoid allocations? I have to
duplicate code anyway
         char[16] buffer;
         buffer = std.string.format(buffer, format, _number);
         sink(buffer);



The idea is to add a format() function that takes sink() for output: 
std.string.format(sink, yourformat, _number);


 Besides, why is it called toString(), if it doesn't give me an object's string
representation???




Should be called debug_output() or something similar.
Apr 23 2009
prev sibling parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Denis Koroskin wrote:

 Sink is okay, but most my usages belong to one of the two scenarios: 
 1) I need a string representation of an Object - how is Sink useful
 here? I just want to call obj.toString() and get the result 2) I need
 to print it to stdout, thus I call writeln/Stdout(obj); - Sink is of
 no use here again.



I hear you, but there are quite a few more considerations that apply.

For one, making string the common format of all objects is pretty 
hamfisted. We need to integrate things like binary streams too. Second, 
using string append and composing with it is bound to be inefficient, 
and for multiple reasons. You can't just say that a reasonable way to 
print a matrix is to call toString against it and print the resulting 
string. With the temporary buffer passed-in or not, that's just a 
terrible design.

But you need not fear. Converting to string will remain easy and simple, 
  it will only be a particular case of streaming objects out.


Andrei
Apr 23 2009
prev sibling next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Don wrote:

 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to slightly 
 improve it is a waste of time -- the whole concept needs to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?



I agree.


 - the object being called has no context. It doesn't know what format is 
 desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.
 
 - it's got no stream concept. Every object has to create and manage its 
 own buffer, and nobody knows if anyone actually needs it.



Yah. std.stdio and std.format already uses streaming internally to some 
extent. I plan to make it entirely possible to dump a string and a 
binary representation of an object to a generic stream, without having 
to allocate any memory in the process.


 It ought to be at least as simple as:
 
 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant string 
 is just going to be written to a file anyway.



Yes. The way it should be is not with sink, but with the standard output 
iterator method put().

void streamOut(T, R)(T object, R range)
{
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
}


 I'd like to see version(debug) {} put around Object.toString(). It's a 
 deathtrap feature that's got no business being used other than for 
 debugging.



Well toString is ok for casual uses, but I agree that true streaming 
mops the floor with it.


Andrei
Apr 23 2009
next sibling parent reply grauzone <none example.net> writes:
 Yes. The way it should be is not with sink, but with the standard output 
 iterator method put().
 
 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



Eh. Is a sink callback too simple and easy to use or what?
Apr 23 2009
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
grauzone wrote:

 Yes. The way it should be is not with sink, but with the standard 
 output iterator method put().

 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



 Eh. Is a sink callback too simple and easy to use or what?



?

Andrei
Apr 23 2009
parent reply grauzone <none example.net> writes:
Andrei Alexandrescu wrote:

 grauzone wrote:

 Yes. The way it should be is not with sink, but with the standard 
 output iterator method put().

 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



 Eh. Is a sink callback too simple and easy to use or what?



 ?



Why make it more complicated than it has to be?
Also, I don't know ranges, but your example doesn't seem to make much sense.


 Andrei
Apr 23 2009
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
grauzone wrote:

 Andrei Alexandrescu wrote:

 grauzone wrote:

 Yes. The way it should be is not with sink, but with the standard 
 output iterator method put().

 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



 Eh. Is a sink callback too simple and easy to use or what?



 ?



 Why make it more complicated than it has to be?



I am making it simpler.


 Also, I don't know ranges, but your example doesn't seem to make much 
 sense.



s/but/consequently/


Andrei
Apr 23 2009
parent reply grauzone <none example.net> writes:
Andrei Alexandrescu wrote:

 grauzone wrote:

 Andrei Alexandrescu wrote:

 grauzone wrote:

 Yes. The way it should be is not with sink, but with the standard 
 output iterator method put().

 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



 Eh. Is a sink callback too simple and easy to use or what?



 ?



 Why make it more complicated than it has to be?



 I am making it simpler.



How is it simpler?

sink(): simple delegate with the signature void delegate(char[] data);
output range: um what...? yeah, I know it has a put() method that 
takes... something. What exactly is it supposed to take in your example? 
Is streamOut() a method of the object to be dumped? What exact types to 
T and R have? (You need the exact type if streamOut is supposed to be a 
member function, and thus has to be virtual, so that you can it use like 
the Object.toString method.)


 Also, I don't know ranges, but your example doesn't seem to make much 
 sense.



 s/but/consequently/



Probably. Just imagine you had to explain it to someone who's new to D. 
Actually, I _am_ new to D2.0.

So, um... what is a b c and T object?


 
 Andrei
Apr 23 2009
parent reply grauzone <none example.net> writes:
Simen Kjaeraas wrote:

 grauzone wrote:
 

 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }















 So, um... what is a b c and T object?



 In my opinion, this is a confusing example. I believe it was meant to be:
 
 void streamOut(T, R)(T object, R range)
 {
  foreach(x; object.a) range.put(x);
  range.put(object.b);
  range.put(object.c);
 }
 
 So, streamOut is a free function, which it normally would not be. Now, 
 consider this:
 
 struct foo {
  int[] a;
  bool b;
  char c;
 
  void streamOut(R)(R range) {
    foreach(x; a) range.put(x);
    range.put(b);
    range.put(c);
  }
 }
 
 I believe this is what you'd normally do.
 
 Do note that I might have misinterpreted it all, as Andrei's code would 
 not do what I have outlined above, I only feel it makes the most sense.



Yeah OK, but what about virtual functions? Not having it virtual is a 
real disadvantage, because subclass-parts aren't automatically dumped. 
What exactly is R, and why is it simpler than a Sink delegate? A Sink 
delegate is as simple as it gets, and what else than a string do you 
want to output? (Hint: this is probably not supposed to be a 
serialization framework.)

One thing that I could imagine that put() automatically takes care of 
formatting various data types into a string. Okay, where can I pass 
format specifiers? What if put() can't deal with the type? Or does it 
call std.string.format() anyway? Then why the indirection through the 
string? Why not call format() directly? (Yes, format() needs to be able 
to output using a sink instead of returning a string.)

Oh by the way, unlike a weird template, sink works with virtual methods, 
too.

I have the impression Andrei wants to cast everything into ranges 
instead of adhering to KISS.


 -- 
  Simen
Apr 24 2009
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
grauzone wrote:

 Simen Kjaeraas wrote:

 Do note that I might have misinterpreted it all, as Andrei's code 
 would not do what I have outlined above, I only feel it makes the most 
 sense.



 Yeah OK, but what about virtual functions? Not having it virtual is a 
 real disadvantage, because subclass-parts aren't automatically dumped.



Streaming out is a virtual function that takes a classic interface 
object. (I explained that in two posts.)


 What exactly is R, and why is it simpler than a Sink delegate? A Sink 
 delegate is as simple as it gets, and what else than a string do you 
 want to output? (Hint: this is probably not supposed to be a 
 serialization framework.)



It is simpler than a Sink delegate because the delegate is not simple; 
it's simplistic. You can't use std.algorithm with a delegate, it only 
accepts one type (meaning it is very inefficient if you have multiple 
types to output) - it's essentially a non-design.


 One thing that I could imagine that put() automatically takes care of 
 formatting various data types into a string. Okay, where can I pass 
 format specifiers? What if put() can't deal with the type? Or does it 
 call std.string.format() anyway? Then why the indirection through the 
 string? Why not call format() directly? (Yes, format() needs to be able 
 to output using a sink instead of returning a string.)



I'd spend more time on explaining that but I fear you want more to 
convince yourself and others that output streams are no good and that 
your non-design is simpler, than actually getting answers to your questions.


 Oh by the way, unlike a weird template, sink works with virtual methods, 
 too.
 
 I have the impression Andrei wants to cast everything into ranges 
 instead of adhering to KISS.



I want to adhere to KISS, and therefore I want to support output ranges 
with e.g. strings and files. If you don't take the time to look at 
ranges as you yourself said, then why do you spend time commenting on 
them? Shouldn't things go the other way?


Andrei
Apr 24 2009
next sibling parent grauzone <none example.net> writes:
Andrei Alexandrescu wrote:

 grauzone wrote:

 Simen Kjaeraas wrote:

 Do note that I might have misinterpreted it all, as Andrei's code 
 would not do what I have outlined above, I only feel it makes the 
 most sense.



 Yeah OK, but what about virtual functions? Not having it virtual is a 
 real disadvantage, because subclass-parts aren't automatically dumped.



 Streaming out is a virtual function that takes a classic interface 
 object. (I explained that in two posts.)



There were a lot of posts in this thread. From what I've gathered, what 
you said wasn't really concrete. Not as concrete as the sink proposals.


 What exactly is R, and why is it simpler than a Sink delegate? A Sink 
 delegate is as simple as it gets, and what else than a string do you 
 want to output? (Hint: this is probably not supposed to be a 
 serialization framework.)



 It is simpler than a Sink delegate because the delegate is not simple; 
 it's simplistic. You can't use std.algorithm with a delegate, it only 
 accepts one type (meaning it is very inefficient if you have multiple 
 types to output) - it's essentially a non-design.



At some point, you need to format it to a string anyway. And it's 
probably not favorable to move that code into some deeply buried library 
code, because then you don't have full control over formatting. Anyway, 
I don't quite understand what you want to do. We were talking abou 
improving toString, right?


 One thing that I could imagine that put() automatically takes care of 
 formatting various data types into a string. Okay, where can I pass 
 format specifiers? What if put() can't deal with the type? Or does it 
 call std.string.format() anyway? Then why the indirection through the 
 string? Why not call format() directly? (Yes, format() needs to be 
 able to output using a sink instead of returning a string.)



 I'd spend more time on explaining that but I fear you want more to 
 convince yourself and others that output streams are no good and that 
 your non-design is simpler, than actually getting answers to your 
 questions.



It's not my design, and I didn't even come up with that proposal. Come 
on, I know my tone and my posts is bitchy as hell, but flaming is not 
really what I'm up to.


 Oh by the way, unlike a weird template, sink works with virtual 
 methods, too.

 I have the impression Andrei wants to cast everything into ranges 
 instead of adhering to KISS.



 I want to adhere to KISS, and therefore I want to support output ranges 
 with e.g. strings and files. If you don't take the time to look at 
 ranges as you yourself said, then why do you spend time commenting on 
 them? Shouldn't things go the other way?



Oh, I look at the Phobos docs as it seems necessary. But I still might 
not know to the fullest how the pieces fit together and so on.


 
 Andrei
Apr 24 2009
prev sibling parent Christopher Wright <dhasenan gmail.com> writes:
Andrei Alexandrescu wrote:

 grauzone wrote:

 Simen Kjaeraas wrote:

 Do note that I might have misinterpreted it all, as Andrei's code 
 would not do what I have outlined above, I only feel it makes the 
 most sense.



 Yeah OK, but what about virtual functions? Not having it virtual is a 
 real disadvantage, because subclass-parts aren't automatically dumped.



 Streaming out is a virtual function that takes a classic interface 
 object. (I explained that in two posts.)
 

 What exactly is R, and why is it simpler than a Sink delegate? A Sink 
 delegate is as simple as it gets, and what else than a string do you 
 want to output? (Hint: this is probably not supposed to be a 
 serialization framework.)



 It is simpler than a Sink delegate because the delegate is not simple; 
 it's simplistic. You can't use std.algorithm with a delegate, it only 
 accepts one type (meaning it is very inefficient if you have multiple 
 types to output) - it's essentially a non-design.



There are two possible use cases: serializing (to a text-based or binary 
format) and formatting.

Serializing won't always fit here. For example, if you want to serialize 
to XML, you need to tell the serializer when you're beginning a tag and 
what to name it and when to end it. This might be possible with ranges, 
but it would be awkward. Or maybe you have different concerns when 
serializing in one binary format versus another. Or you're outputting 
JSON, and you could view something as an array of objects or as a single 
object -- you need to specify that.

Formatting is the other concern. This is a special case of 
non-hierarchical serialization, for which ranges could work.

However, formatting *has* to be general. I rarely need to override a 
formatting method, but I often need to access something via an interface 
or base class and format it. If this does not work, then toString is 
vastly superior. And to gain the benefits you're talking about, I have 
to be able to pass in different output streams.

You can get the first requirement by having a method that takes a 
formatting struct on Object, but then object.d depends on formatting -- 
this isn't a reasonable situation. object.d can at most define an 
interface for a formatting method:

interface OutStream { ... }
class Object
{
	...
	void print (string format, OutStream stream);
}

This is still pushing it.

An alternative is to have:
void Object.print (void delegate (...) sink);
Apr 24 2009
prev sibling next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 09:06:38 -0400, Andrei Alexandrescu 
 <SeeWebsiteForEmail erdani.org> wrote:
 

 It ought to be at least as simple as:
  struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant 
 string is just going to be written to a file anyway.



 Yes. The way it should be is not with sink, but with the standard 
 output iterator method put().

 void streamOut(T, R)(T object, R range)
 {
      foreach(x; a) range.put(x);
      range.put(b);
      range.put(c);
 }



 What is the T object for?



Red herring. If streamOut is a member, no need for T.


 This has to go into object.d and be part of the runtime, where std.range 
 doesn't exist.  There is nothing stopping you from calling:
 
 streamOut(&outputrange.put);
 
 So I'd rather have a sink function.



It must be a sink _object_ so it can hold its own state. And it must 
support put() so it integrates with statically-bound output ranges.

interface OutRange
{
     void put(... a number of overloads ...);
}


 And I wholeheartedly agree that we need this.  I've run into many 
 situations where toString makes no sense.



Same here...


Andrei
Apr 23 2009
next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 09:24:59 -0400, Andrei Alexandrescu 
 <SeeWebsiteForEmail erdani.org> wrote:
 

 Steven Schveighoffer wrote:

 This has to go into object.d and be part of the runtime, where 
 std.range doesn't exist.  There is nothing stopping you from calling:
  streamOut(&outputrange.put);
  So I'd rather have a sink function.



 It must be a sink _object_ so it can hold its own state. And it must 
 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
      void put(... a number of overloads ...);
 }



 I see now, yes I agree (I think that was don's original request 
 anyways).  That interface has to go in the runtime, though.
 
 We may not be able to do this using templates... it has to be a virtual 
 function in Object to be on-par with toString.  This means struct 
 interfaces are a requirement if you want to use ranges :(



We're in good shape actually. OutRange as a dynamic interface and an 
implicit interface using .put against a struct will work just as well 
with templates. (The template doesn't care whether obj.put(x) is a 
virtual call or statically-bound call.)

Andrei
Apr 23 2009
parent reply Daniel Keep <daniel.keep.lists gmail.com> writes:
Andrei Alexandrescu wrote:

 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 09:24:59 -0400, Andrei Alexandrescu
 <SeeWebsiteForEmail erdani.org> wrote:


 Steven Schveighoffer wrote:

 This has to go into object.d and be part of the runtime, where
 std.range doesn't exist.  There is nothing stopping you from calling:
  streamOut(&outputrange.put);
  So I'd rather have a sink function.



 It must be a sink _object_ so it can hold its own state. And it must
 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
      void put(... a number of overloads ...);
 }



 I see now, yes I agree (I think that was don's original request
 anyways).  That interface has to go in the runtime, though.

 We may not be able to do this using templates... it has to be a
 virtual function in Object to be on-par with toString.  This means
 struct interfaces are a requirement if you want to use ranges :(



 We're in good shape actually. OutRange as a dynamic interface and an
 implicit interface using .put against a struct will work just as well
 with templates. (The template doesn't care whether obj.put(x) is a
 virtual call or statically-bound call.)
 
 Andrei



"We may not be able to do this using templates... it has to be a virtual
function in Object to be on-par with toString."

Note that toString is a virtual method.  You are proposing replacing
toString with a template.  You cannot have virtual template methods.
Ergo, "new toString" would be inaccessible without the actual type, and
certainly not at runtime.

  -- Daniel
Apr 23 2009
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Daniel Keep wrote:

 
 Andrei Alexandrescu wrote:

 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 09:24:59 -0400, Andrei Alexandrescu
 <SeeWebsiteForEmail erdani.org> wrote:


 Steven Schveighoffer wrote:

 This has to go into object.d and be part of the runtime, where
 std.range doesn't exist.  There is nothing stopping you from calling:
  streamOut(&outputrange.put);
  So I'd rather have a sink function.



 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
      void put(... a number of overloads ...);
 }



 anyways).  That interface has to go in the runtime, though.

 We may not be able to do this using templates... it has to be a
 virtual function in Object to be on-par with toString.  This means
 struct interfaces are a requirement if you want to use ranges :(



 implicit interface using .put against a struct will work just as well
 with templates. (The template doesn't care whether obj.put(x) is a
 virtual call or statically-bound call.)

 Andrei



 "We may not be able to do this using templates... it has to be a virtual
 function in Object to be on-par with toString."
 
 Note that toString is a virtual method.  You are proposing replacing
 toString with a template.  You cannot have virtual template methods.
 Ergo, "new toString" would be inaccessible without the actual type, and
 certainly not at runtime.



The toStream that I have in mind is virtual and takes an interface of 
type OutRange as outlined above.

Andrei
Apr 23 2009
parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Steven Schveighoffer wrote:

   As most ranges are structs (and rightfully
 so, who wants to call 3 virtual functions every loop!), they would have 
 to be wrapped under the current compiler. Or am I missing something else?



Yes, some wrapping would have to be done. Hopefully it will simple 
enough to keep things appealingly easy:

obj.toString(dynaRange(range));


Andrei
Apr 23 2009
prev sibling parent reply Frits van Bommel <fvbommel REMwOVExCAPSs.nl> writes:
Andrei Alexandrescu wrote:

 Steven Schveighoffer wrote:

 So I'd rather have a sink function.



 It must be a sink _object_ so it can hold its own state. And it must 
 support put() so it integrates with statically-bound output ranges.
 
 interface OutRange
 {
     void put(... a number of overloads ...);
 }



What exactly is the problem with requiring the input to the sink to be a string 
(or actually const(char)[])?
Requiring an overload for every basic type + Object would be quite cumbersome
if 
you had to do it every time you want to send the output somewhere else. Also,
it 
wouldn't work for structs and unions...
(Unless you plan to implement a default OutRange that converts everything it 
gets to strings and passes it on?)
Apr 23 2009
parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Frits van Bommel wrote:

 Andrei Alexandrescu wrote:

 Steven Schveighoffer wrote:

 So I'd rather have a sink function.



 It must be a sink _object_ so it can hold its own state. And it must 
 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
     void put(... a number of overloads ...);
 }



 What exactly is the problem with requiring the input to the sink to be a 
 string (or actually const(char)[])?



You'd be forced to use intermediate strings for everything. I guess it's 
not a huge concern.


 Requiring an overload for every basic type + Object would be quite 
 cumbersome if you had to do it every time you want to send the output 
 somewhere else. Also, it wouldn't work for structs and unions...
 (Unless you plan to implement a default OutRange that converts 
 everything it gets to strings and passes it on?)



I'm thinking of only allowing a few fundamental types and then have user 
code build the rest using them.


Andrei
Apr 23 2009
prev sibling parent Christopher Wright <dhasenan gmail.com> writes:
Andrei Alexandrescu wrote:

 Yes. The way it should be is not with sink, but with the standard output 
 iterator method put().
 
 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }



// object.d
class Object
{
	void streamOut(R)(R range);
}

No?
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 09:06:38 -0400, Andrei Alexandrescu  
<SeeWebsiteForEmail erdani.org> wrote:


 It ought to be at least as simple as:
  struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your  
 strings in, even if there are 200 million of them and your giant string  
 is just going to be written to a file anyway.



 Yes. The way it should be is not with sink, but with the standard output  
 iterator method put().

 void streamOut(T, R)(T object, R range)
 {
      foreach(x; a) range.put(x);
      range.put(b);
      range.put(c);
 }



What is the T object for?

This has to go into object.d and be part of the runtime, where std.range  
doesn't exist.  There is nothing stopping you from calling:

streamOut(&outputrange.put);

So I'd rather have a sink function.

And I wholeheartedly agree that we need this.  I've run into many  
situations where toString makes no sense.

-Steve
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 09:24:59 -0400, Andrei Alexandrescu  
<SeeWebsiteForEmail erdani.org> wrote:


 Steven Schveighoffer wrote:

 This has to go into object.d and be part of the runtime, where  
 std.range doesn't exist.  There is nothing stopping you from calling:
  streamOut(&outputrange.put);
  So I'd rather have a sink function.



 It must be a sink _object_ so it can hold its own state. And it must  
 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
      void put(... a number of overloads ...);
 }



I see now, yes I agree (I think that was don's original request anyways).   
That interface has to go in the runtime, though.

We may not be able to do this using templates... it has to be a virtual  
function in Object to be on-par with toString.  This means struct  
interfaces are a requirement if you want to use ranges :(

-Steve
Apr 23 2009
prev sibling next sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it 
 and its new Phobos2. While I explore Phobos I'll probably post some 
 comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than 
 the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times is 
 just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to slightly 
 improve it is a waste of time -- the whole concept needs to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?
 
 - the object being called has no context. It doesn't know what format is 
 desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.
 
 - it's got no stream concept. Every object has to create and manage its 
 own buffer, and nobody knows if anyone actually needs it.
 
 It ought to be at least as simple as:
 
 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant string 
 is just going to be written to a file anyway.
 
 I'd like to see version(debug) {} put around Object.toString(). It's a 
 deathtrap feature that's got no business being used other than for 
 debugging.
 </rant>



First of all, printing stuff "struct.toString()" style is for two things:

  o  Debugging
  o  Small throwaway code snippets

The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

No "Real Program" uses this, because there you typically do proper 
formatting of the output anyway, and almost never print entire structs 
or objects as such. Instead, rather the information that they represent.



Second, since we have cool stuff in D, like templates, boxing, and other 
advanced things, then compared to them, it should not be a big deal to 
have automatic creation of toString for structs and objects. (This could 
even be on-demand, i.e. unless called, the toString is not created for 
an object/struct.)

Since the purpose of toString here is not Grand Style, it should suffice 
to just recursively print the struct with its possible substructs, etc.

This would relieve the programmer from the entire extra work, and it 
would also make objects look tidyer in source code.

Actually, this way, it would become trivial to print stuff:

myFancyStructWithInnerStructs st;
myRealCoolObject mo;
int i;
float f;
string s;

writeln(st,mo,i,f,s);

Here the programmer couldn't care less about looks and formatting, *as 
long as* the output is legible and clear.

And what luxury -- not having to update the toString function each time 
you change the class' structure! (That's a relief in the early stages of 
the program, when everything is alive and fluid, before one settles on 
the optimum structure.)

Naturally, if the programmer *does* supply a toString() method, then 
that'd be used instead.

--------

Another way to do this would be to have a template function that writeln 
(but not writefln) calls, which introspects the printee, and prints it.
Apr 23 2009
next sibling parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Georg Wrede wrote:

 Second, since we have cool stuff in D, like templates, boxing, and other 
 advanced things, then compared to them, it should not be a big deal to 
 have automatic creation of toString for structs and objects. (This could 
 even be on-demand, i.e. unless called, the toString is not created for 
 an object/struct.)
 
 Since the purpose of toString here is not Grand Style, it should suffice 
 to just recursively print the struct with its possible substructs, etc.
 
 This would relieve the programmer from the entire extra work, and it 
 would also make objects look tidyer in source code.



Did you know that this:

#!/home/andrei/bin/rdmd
import std.conv, std.stdio;

struct S1
{
     int a = 42;
     S2 b;
}

struct S2
{
     int x = 4;
     float y = 5.5;
}

void main()
{
     writeln(to!string(S1()));
}

prints this

S1(42, S2(4, 5.5))

?


Andrei
Apr 23 2009
parent reply Georg Wrede <georg.wrede iki.fi> writes:
Andrei Alexandrescu wrote:

 Georg Wrede wrote:

 Second, since we have cool stuff in D, like templates, boxing, and 
 other advanced things, then compared to them, it should not be a big 
 deal to have automatic creation of toString for structs and objects. 
 (This could even be on-demand, i.e. unless called, the toString is not 
 created for an object/struct.)

 Since the purpose of toString here is not Grand Style, it should 
 suffice to just recursively print the struct with its possible 
 substructs, etc.

 This would relieve the programmer from the entire extra work, and it 
 would also make objects look tidyer in source code.



 Did you know that this:
 
 #!/home/andrei/bin/rdmd
 import std.conv, std.stdio;
 
 struct S1
 {
     int a = 42;
     S2 b;
 }
 
 struct S2
 {
     int x = 4;
     float y = 5.5;
 }
 
 void main()
 {
     writeln(to!string(S1()));
 }
 
 prints this
 
 S1(42, S2(4, 5.5))



Wow!

What if writeln would automatically call to!string for any object or struct?
Apr 23 2009
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
Georg Wrede wrote:

 Wow!
 
 What if writeln would automatically call to!string for any object or 
 struct?



That's the plan, I didn't get around to it. I want to do it the right 
way, i.e. with general streams, not strings.

Andrei
Apr 23 2009
parent Georg Wrede <georg.wrede iki.fi> writes:
Andrei Alexandrescu wrote:

 Georg Wrede wrote:

 Wow!

 What if writeln would automatically call to!string for any object or 
 struct?



 That's the plan, I didn't get around to it. I want to do it the right 
 way, i.e. with general streams, not strings.



I'm just impressed.
Apr 23 2009
prev sibling next sibling parent reply Don <nospam nospam.com> writes:
Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it 
 and its new Phobos2. While I explore Phobos I'll probably post some 
 comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {






 

 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than 
 the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times 
 is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to 
 slightly improve it is a waste of time -- the whole concept needs to 
 be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?

 - the object being called has no context. It doesn't know what format 
 is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.

 - it's got no stream concept. Every object has to create and manage 
 its own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant 
 string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString(). It's a 
 deathtrap feature that's got no business being used other than for 
 debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two things:
 
  o  Debugging
  o  Small throwaway code snippets
 
 The latter mainly being for two purposes:
 
  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.
 
 No "Real Program" uses this, because there you typically do proper 
 formatting of the output anyway, and almost never print entire structs 
 or objects as such. Instead, rather the information that they represent.



How about something like BigInt? Why can't you just print it out?

BTW to everyone, 'Sink' was not a proposal. I was just saying that 
almost anything's better than the current toString().
Apr 23 2009
parent reply Georg Wrede <georg.wrede iki.fi> writes:
Don wrote:

 Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it 
 and its new Phobos2. While I explore Phobos I'll probably post some 
 comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than 
 the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times 
 is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to 
 slightly improve it is a waste of time -- the whole concept needs to 
 be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?

 - the object being called has no context. It doesn't know what format 
 is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.

 - it's got no stream concept. Every object has to create and manage 
 its own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant 
 string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString(). It's 
 a deathtrap feature that's got no business being used other than for 
 debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two things:

  o  Debugging
  o  Small throwaway code snippets

 The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

 No "Real Program" uses this, because there you typically do proper 
 formatting of the output anyway, and almost never print entire structs 
 or objects as such. Instead, rather the information that they represent.



 How about something like BigInt? Why can't you just print it out?



?? Why couldn't you?

They're not stored as strings (not Janice's anyway), but I don't 
understand the question.


 BTW to everyone, 'Sink' was not a proposal. I was just saying that 
 almost anything's better than the current toString().
Apr 23 2009
parent reply Don <nospam nospam.com> writes:
Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest it 
 and its new Phobos2. While I explore Phobos I'll probably post some 
 comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better than 
 the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most times 
 is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to 
 slightly improve it is a waste of time -- the whole concept needs to 
 be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What more 
 could there be to hate?

 - the object being called has no context. It doesn't know what 
 format is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.

 - it's got no stream concept. Every object has to create and manage 
 its own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant 
 string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString(). It's 
 a deathtrap feature that's got no business being used other than for 
 debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two 
 things:

  o  Debugging
  o  Small throwaway code snippets

 The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

 No "Real Program" uses this, because there you typically do proper 
 formatting of the output anyway, and almost never print entire 
 structs or objects as such. Instead, rather the information that they 
 represent.



 How about something like BigInt? Why can't you just print it out?



 ?? Why couldn't you?
 
 They're not stored as strings (not Janice's anyway), but I don't 
 understand the question.



You can write:

int a, b;
a=10; b=20;
writefln("%d %x", a, b);

I'd like to be able to write:

BigInt a, b;
a=10; b=20;
writefln("%d %x", a, b);

and have it behave exactly the same.



 

 BTW to everyone, 'Sink' was not a proposal. I was just saying that 
 almost anything's better than the current toString().
Apr 23 2009
parent reply Georg Wrede <georg.wrede iki.fi> writes:
Don wrote:

 Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest 
 it and its new Phobos2. While I explore Phobos I'll probably post 
 some comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better 
 than the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most 
 times is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to 
 slightly improve it is a waste of time -- the whole concept needs 
 to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What 
 more could there be to hate?

 - the object being called has no context. It doesn't know what 
 format is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! You 
 can't do left-align, pad with zeros, include + sign, display in hex.

 - it's got no stream concept. Every object has to create and manage 
 its own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your 
 strings in, even if there are 200 million of them and your giant 
 string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString(). 
 It's a deathtrap feature that's got no business being used other 
 than for debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two 
 things:

  o  Debugging
  o  Small throwaway code snippets

 The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

 No "Real Program" uses this, because there you typically do proper 
 formatting of the output anyway, and almost never print entire 
 structs or objects as such. Instead, rather the information that 
 they represent.



 How about something like BigInt? Why can't you just print it out?



 ?? Why couldn't you?

 They're not stored as strings (not Janice's anyway), but I don't 
 understand the question.



 You can write:
 
 int a, b;
 a=10; b=20;
 writefln("%d %x", a, b);
 
 I'd like to be able to write:
 
 BigInt a, b;
 a=10; b=20;
 writefln("%d %x", a, b);
 
 and have it behave exactly the same.




Hmm. My idea was to only have writeln (and not writefln) be automated. 
(For the small/debugging purpose.)

Andrei seems to be at this, but right now I don't know enough details to 
say anything. It seems to be an even bigger thing than what I suggested, 
and knowing he does things in a universal way, one would assume that if 
a class "wants" to be printed in some way, then maybe there'll be some 
provisions for it.

But, things like BigInt, that really are classes or structs that have to 
be printed in a specific way, I have a hard time figuring out how to 
printe them using write_f_ln.

One way would be to have the format specification (as in "%x") be 
somehow passed to the toString of the struct/class. Then the class could 
decide for itself how to be printed in this case.


But even this is stretching it a bit, since some more complicated 
class/struct might need a more elaborate hint than just one letter. And 
by that time the whole thing starts to crumble, in usability issues, at 
least.

One thing we sholuld be wary of is overdesign. BigInt is ok, but by the 
time we try to include a class called CompleteSimulationOfAnF1RaceCar, 
we're screwed. :-)  I see no way to incorporate them into writefln or 
even plain writeln. Or at least, no *use*.
Apr 23 2009
parent reply Don <nospam nospam.com> writes:
Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest 
 it and its new Phobos2. While I explore Phobos I'll probably post 
 some comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx 

 I have tried to write a toy implementation of it in D2 (not using 
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good 
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better 
 than the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most 
 times is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to 
 slightly improve it is a waste of time -- the whole concept needs 
 to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What 
 more could there be to hate?

 - the object being called has no context. It doesn't know what 
 format is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int! 
 You can't do left-align, pad with zeros, include + sign, display 
 in hex.

 - it's got no stream concept. Every object has to create and 
 manage its own buffer, and nobody knows if anyone actually needs it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all 
 your strings in, even if there are 200 million of them and your 
 giant string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString(). 
 It's a deathtrap feature that's got no business being used other 
 than for debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two 
 things:

  o  Debugging
  o  Small throwaway code snippets

 The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

 No "Real Program" uses this, because there you typically do proper 
 formatting of the output anyway, and almost never print entire 
 structs or objects as such. Instead, rather the information that 
 they represent.



 How about something like BigInt? Why can't you just print it out?



 ?? Why couldn't you?

 They're not stored as strings (not Janice's anyway), but I don't 
 understand the question.



 You can write:

 int a, b;
 a=10; b=20;
 writefln("%d %x", a, b);

 I'd like to be able to write:

 BigInt a, b;
 a=10; b=20;
 writefln("%d %x", a, b);

 and have it behave exactly the same.



 
 Hmm. My idea was to only have writeln (and not writefln) be automated. 
 (For the small/debugging purpose.)
 
 Andrei seems to be at this, but right now I don't know enough details to 
 say anything. It seems to be an even bigger thing than what I suggested, 
 and knowing he does things in a universal way, one would assume that if 
 a class "wants" to be printed in some way, then maybe there'll be some 
 provisions for it.
 
 But, things like BigInt, that really are classes or structs that have to 
 be printed in a specific way, I have a hard time figuring out how to 
 printe them using write_f_ln.
 
 One way would be to have the format specification (as in "%x") be 
 somehow passed to the toString of the struct/class. Then the class could 
 decide for itself how to be printed in this case.
 
 
 But even this is stretching it a bit, since some more complicated 
 class/struct might need a more elaborate hint than just one letter. And 
 by that time the whole thing starts to crumble, in usability issues, at 
 least.
 
 One thing we sholuld be wary of is overdesign. BigInt is ok, but by the 
 time we try to include a class called CompleteSimulationOfAnF1RaceCar, 
 we're screwed. :-)  I see no way to incorporate them into writefln or 
 even plain writeln. Or at least, no *use*.



I think it'd be reasonable to limit things to the options available for 
built-in types. Outside of that, custom formatting functions make a lot 
of sense. The problem is that toString() _looks_ like it emulates 
built-in formatting, but it only does '%s'. So it's really beguiling.

BTW, when passing the output to a sink, it should be possible to (say) 
format your members with '%x' format, but you can't do that by 
permanently altering sink: it should revert to its previous value once 
you've sunk your last member. (I think this C++ iostreams got this wrong).
Apr 23 2009
parent reply Georg Wrede <georg.wrede iki.fi> writes:
Don wrote:

 Georg Wrede wrote:

 One thing we sholuld be wary of is overdesign. BigInt is ok, but by 
 the time we try to include a class called 
 CompleteSimulationOfAnF1RaceCar, we're screwed. :-)  I see no way to 
 incorporate them into writefln or even plain writeln. Or at least, no 
 *use*.



 I think it'd be reasonable to limit things to the options available for 
 built-in types. Outside of that, custom formatting functions make a lot 
 of sense. The problem is that toString() _looks_ like it emulates 
 built-in formatting, but it only does '%s'. So it's really beguiling.



Heh, one thought is, suppose we could have arbitrary format 
specifications in writef. Say, if we wrote %&lkjasdf; this string would 
be passed to toString. (It would of course be up to the class to 
error-check the string, writefln obviously cant (or shouldn't) do it.)

So, things are doable. But I'm really not looking forward to that kind 
of sports. Any elaborate printing or formatting should be handled 
outside writefln &co.


 BTW, when passing the output to a sink, it should be possible to (say) 
 format your members with '%x' format, but you can't do that by 
 permanently altering sink: it should revert to its previous value once 
 you've sunk your last member. (I think this C++ iostreams got this wrong).



I guess they, too, thought of making it "easier" in the wrong place. 
Just because you can, doesn't mean you have to.

(OT: an excellent example of this It's Done Because We Noticed We Could 
stuff is in Firefox. When a picture is a link to another page, and you 
want to drag that to the tab area, the entire picture is dragged with 
the mouse. Now, how the hell am I supposed to hit the small tab area 
when the large picture covers half of my Firefox??

So now I have to learn to remember to grab bigger pictures near some 
edge. And I really can't see *any* valid benefit for having to drag the 
picture. I'd rather have it the old way, where the mouse pointer simply 
changes shape, so you know you're dragging. Damn, damn...)
Apr 23 2009
next sibling parent "Joel C. Salomon" <joelcsalomon gmail.com> writes:
Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 One thing we sholuld be wary of is overdesign. BigInt is ok, but by
 the time we try to include a class called
 CompleteSimulationOfAnF1RaceCar, we're screwed. :-)  I see no way to
 incorporate them into writefln or even plain writeln. Or at least, no
 *use*.



 I think it'd be reasonable to limit things to the options available
 for built-in types. Outside of that, custom formatting functions make
 a lot of sense. The problem is that toString() _looks_ like it
 emulates built-in formatting, but it only does '%s'. So it's really
 beguiling.



 Heh, one thought is, suppose we could have arbitrary format
 specifications in writef. Say, if we wrote %&lkjasdf; this string would
 be passed to toString. (It would of course be up to the class to
 error-check the string, writefln obviously cant (or shouldn't) do it.)
 
 So, things are doable. But I'm really not looking forward to that kind
 of sports. Any elaborate printing or formatting should be handled
 outside writefln &co.



Take a look at the formatting library for Plan 9.  It’s very much like
printf & co., except it exposes enough of its internals to allow for new
formats to be added in.  See the documentation (for the *nix-ported
version) at <http://swtch.com/plan9port/man/man3/print.html> and
<http://swtch.com/plan9port/man/man3/fmtinstall.html>. For example:

typedef
struct {
	double	r, i;
} Complex;
#pragma  varargck  type "X"  Complex	// compiler checks type-safety

int
Xfmt(Fmt *f)
{
	Complex c;
	c = va_arg(f−>args, Complex);
	return fmtprint(f, "(%g,%g)", c.r, c.i); // can use flags here
}

main(...)
{
	Complex x = (Complex){ 1.5, −2.3 };
	fmtinstall('X', Xfmt);
	print("x = %X\n", x);
}

With D’s type-safe variadic functions, this model can be made really
powerful.

—Joel Salomon
Apr 23 2009
prev sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 12:09:20 -0400, Georg Wrede <georg.wrede iki.fi> wrote:
 

 (OT: an excellent example of this It's Done Because We Noticed We 
 Could stuff is in Firefox. When a picture is a link to another page, 
 and you want to drag that to the tab area, the entire picture is 
 dragged with the mouse. Now, how the hell am I supposed to hit the 
 small tab area when the large picture covers half of my Firefox??

 So now I have to learn to remember to grab bigger pictures near some 
 edge. And I really can't see *any* valid benefit for having to drag 
 the picture. I'd rather have it the old way, where the mouse pointer 
 simply changes shape, so you know you're dragging. Damn, damn...)



 On my system, dragging the image drags a translucent copy of the image, 
 so I can still see where my mouse pointer is aimed.  Maybe you don't 
 have enough colors enabled on your screen?



Sure it looks good, and the computer owner can brag to the guy in the 
next cubicle, etc. But there should be some obvious or useful *purpose* 
for dragging entire pictures where a mouse pointer would be clearer, 
cleaner, easier for the user, and use less computer cycles.

I mean, who's such a nutcase that he forgets halfway in the dragging, 
what it is he's dragging?
Apr 23 2009
next sibling parent reply "Nick Sabalausky" <a a.a> writes:
"Steven Schveighoffer" <schveiguy yahoo.com> wrote in message 
news:op.usux6bskeav7ka steves.networkengines.com...

 I was never a huge fan of application themes.  I don't mind a theme for 
 the whole system (as long as it's simple), but I don't want iTunes to look 
 different just because it can.



That's one of my biggest pet peeves about modern software. I can't really do 
the subject justice without delving into a giant pile of expletives. But 
worse still is when they decide to go and piss all over not just standard 
looks, but also standard behaviors. Like how the Win build of iTunes will 
still ignore/"eat" any click that brings it to the foreground. If I wanted 
that behavior I'd be running a Mac.

The absolute worst of all though is when an app (*cough* skype *cough*) 
decides that "close" and "the 'close' button" should mean "don't close 
anything at all, but minimize to tray instead". That should be a firing 
squad offense ;) Joking aside though, any of these are guaranteed ways to 
make me lose any and all respect for a piece of software and its developers, 
especially if they're arrogant enough to provide no way to turn such things 
off.
Apr 23 2009
next sibling parent reply Christopher Wright <dhasenan gmail.com> writes:
Nick Sabalausky wrote:

 "Steven Schveighoffer" <schveiguy yahoo.com> wrote in message 
 news:op.usux6bskeav7ka steves.networkengines.com...

 I was never a huge fan of application themes.  I don't mind a theme for 
 the whole system (as long as it's simple), but I don't want iTunes to look 
 different just because it can.



 That's one of my biggest pet peeves about modern software. I can't really do 
 the subject justice without delving into a giant pile of expletives. But 
 worse still is when they decide to go and piss all over not just standard 
 looks, but also standard behaviors. Like how the Win build of iTunes will 
 still ignore/"eat" any click that brings it to the foreground. If I wanted 
 that behavior I'd be running a Mac.
 
 The absolute worst of all though is when an app (*cough* skype *cough*) 
 decides that "close" and "the 'close' button" should mean "don't close 
 anything at all, but minimize to tray instead". That should be a firing 
 squad offense ;)



I'd be killing my IM client constantly if not for that feature. I pretty 
much expect it of any application that's meant to be running for a long 
time and only rarely needing user interaction (such as a bittorrent client).
Apr 23 2009
next sibling parent reply BCS <none anon.com> writes:
Hello Christopher,


 Nick Sabalausky wrote:
  

 The absolute worst of all though is when an app (*cough* skype
 *cough*) decides that "close" and "the 'close' button" should mean
 "don't close anything at all, but minimize to tray instead". That
 should be a firing squad offense ;)
 



 pretty much expect it of any application that's meant to be running
 for a long time and only rarely needing user interaction (such as a
 bittorrent client).
 



yah, for some programs you rarely want to close the program but often want 
to close the UI.
Apr 23 2009
next sibling parent Daniel Keep <daniel.keep.lists gmail.com> writes:
BCS wrote:

 Hello Christopher,
 

 Nick Sabalausky wrote:
  

 The absolute worst of all though is when an app (*cough* skype
 *cough*) decides that "close" and "the 'close' button" should mean
 "don't close anything at all, but minimize to tray instead". That
 should be a firing squad offense ;)



 pretty much expect it of any application that's meant to be running
 for a long time and only rarely needing user interaction (such as a
 bittorrent client).



 yah, for some programs you rarely want to close the program but often
 want to close the UI.



This is one place where I think Mac OS X gets it right.  It's a massive
pain to close the last document open in OpenOffice.org before opening a
new one, only to realise that now you have to sit through the loading
screen again.

  -- Daniel
Apr 23 2009
prev sibling parent reply "Nick Sabalausky" <a a.a> writes:
"BCS" <none anon.com> wrote in message 
news:a6268ff50558cb92691721562e news.digitalmars.com...

 Hello Christopher,


 Nick Sabalausky wrote:


 The absolute worst of all though is when an app (*cough* skype
 *cough*) decides that "close" and "the 'close' button" should mean
 "don't close anything at all, but minimize to tray instead". That
 should be a firing squad offense ;)



 pretty much expect it of any application that's meant to be running
 for a long time and only rarely needing user interaction (such as a
 bittorrent client).



 yah, for some programs you rarely want to close the program but often want 
 to close the UI.



That's called "Minimize".
Apr 24 2009
next sibling parent reply BCS <none anon.com> writes:
Hello Nick,


 "BCS" <none anon.com> wrote in message
 news:a6268ff50558cb92691721562e news.digitalmars.com...
 

 yah, for some programs you rarely want to close the program but often
 want to close the UI.
 



 



It can be, OTOH I might want the UI process killed without killing the main 
program. Another point is the other side of the assertion, "you rarely want 
to close the program" as in 90% of the time even when I hit the x button, 
I don't actually want to close the program.
Apr 24 2009
parent reply "Nick Sabalausky" <a a.a> writes:
"BCS" <none anon.com> wrote in message 
news:a6268ff50d58cb92d952e5b612 news.digitalmars.com...

 Hello Nick,


 "BCS" <none anon.com> wrote in message
 news:a6268ff50558cb92691721562e news.digitalmars.com...


 yah, for some programs you rarely want to close the program but often
 want to close the UI.






 It can be, OTOH I might want the UI process killed without killing the 
 main program. Another point is the other side of the assertion, "you 
 rarely want to close the program" as in 90% of the time even when I hit 
 the x button, I don't actually want to close the program.



The whole point of the 'x' button is the close the program. Always has been. 
If I didn't want to close the program, I wouldn't push it. If you want to 
hide/kill the UI without closing the program, that's "minimize". True, 
minimizing to the taskbar doesn't kill the UI process/thread (assuming it 
even is a separate process/thread), but in the rare cases where the 
distinction of "UI process running/killed" actually matters, the program can 
still do that through a minimize to tray. And while neither "minimize" nor 
"close" truly mean "minimize to tray", clearly "minimize" is FAR closer in 
both wording and behavior. Any way you look at it, having a "close" button 
that doesn't "close" the app is like having a "cancel" button that prints, 
or a "save" button that plays music.
Apr 24 2009
parent reply BCS <ao pathlink.com> writes:
Reply to Nick,


 "BCS" <none anon.com> wrote in message
 news:a6268ff50d58cb92d952e5b612 news.digitalmars.com...
 

 Hello Nick,
 

 "BCS" <none anon.com> wrote in message
 news:a6268ff50558cb92691721562e news.digitalmars.com...

 yah, for some programs you rarely want to close the program but
 often want to close the UI.
 



 



 the main program. Another point is the other side of the assertion,
 "you rarely want to close the program" as in 90% of the time even
 when I hit the x button, I don't actually want to close the program.
 



 been. If I didn't want to close the program, I wouldn't push it.



Are you saying you never make mistakes? There are program out there that 
90% of the time when I hit the x button it was a mistake and in that cases 
I think it to be a good design to work around it. I guess if you really hate 
having it not kill the app then the program could just not /have/ a x button.


 If you want to hide/kill the UI without closing the program, that's
 "minimize". True, minimizing to the taskbar doesn't kill the UI
 process/thread (assuming it even is a separate process/thread), but in
 the rare cases where the distinction of "UI process running/killed"
 actually matters, the program can still do that through a minimize to
 tray. And while neither "minimize" nor "close" truly mean "minimize to
 tray", clearly "minimize" is FAR closer in both wording and behavior.
 Any way you look at it, having a "close" button that doesn't "close"
 the app is like having a "cancel" button that prints, or a "save"
 button that plays music.
 



Your missing my point. I don't want to re-task the button but make it not 
do something that most of the time is not what I want.
Apr 24 2009
next sibling parent reply Christopher Wright <dhasenan gmail.com> writes:
BCS wrote:

 I guess if you 
 really hate having it not kill the app then the program could just not 
 /have/ a x button.



Your window manager does not support such windows.
Apr 24 2009
parent BCS <ao pathlink.com> writes:
Reply to Christopher,


 BCS wrote:
 

 I guess if you really hate having it not kill the app then the
 program could just not /have/ a x button.
 



 



So I guess we're stuck with the no-close close button if we don't want any 
way to close the app in a single click.
Apr 24 2009
prev sibling parent reply "Nick Sabalausky" <a a.a> writes:
"BCS" <ao pathlink.com> wrote in message 
news:78ccfa2d3ebc18cb92e7b8abed64 news.digitalmars.com...

 Are you saying you never make mistakes? There are program out there that 
 90% of the time when I hit the x button it was a mistake and in that cases 
 I think it to be a good design to work around it.



?? Not only can I honestly say I've never had that problem, but I find the 
whole idea of it very strange. Are you certain that your mouse or window 
manager isn't just acting up?


 I guess if you really hate having it not kill the app then the program 
 could just not /have/ a x button.



You've got to be kidding me, that would be just as bad. Why would I want to 
have a program get rid of the standard "exit" mechanism? Whever I come 
across an app like that, the first thing I do is open the task manager and 
kill it, and then immediately uninstall it.


 Your missing my point. I don't want to re-task the button but make it not 
 do something that most of the time is not what I want.



In this particular case, that's exactly the same thing. It's the 
"close"/"exit" button. If it doesn't "close"/"exit" then it's been 
re-tasked. Either to "minimize to tray" or to "noop" or whatever.
Apr 24 2009
parent BCS <none anon.com> writes:
Hello Nick,


 I guess if you really hate having it not kill the app then the
 program could just not /have/ a x button.
 



 want to have a program get rid of the standard "exit" mechanism?



If you basicly never want to exit it? (see below)


 Whever I come across an app like that, the first thing I do is open
 the task manager and kill it, and then immediately uninstall it.



I'll grant there are only very few cases where I want it, but in those cases 
I wouldn't have the program at all unless I wanted it running *all the time*. 
If I found myself killing/restarting the program more than rarely, I'd git 
rid of it and find one I don't have to do that with. For those apps, I
basically 
never want to actually close them (even less often than I reboot) and on 
the few occasions when I do, I'm willing to do file->exit->"Yes I really 
do" sequence.

As an example of a program that works this way that I'll bet you don't mind: 
The volume control in the system tray. I'm not even sure if there /is/ a 
way to close it all the way.

To put it objectively: say the program take 10 sec to reload and 90% of the 
time (I'd bet that's low) that I click the x button, it was a mistake (bad 
mouse control, reflex "go way action", whatever). From that it can take 90 
seconds to close the program before tuning off the x button is a net loss 
(as long as it's easy to figure out how to really kill it).

We may have to agree to disagree; I use a few programs where having the x 
button kill them would be a bad thing IMHO. You disagreeing really doesn't 
matter to me.
Apr 25 2009
prev sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Fri, 24 Apr 2009 14:00:19 -0400, Nick Sabalausky <a a.a> wrote:


 "BCS" <none anon.com> wrote in message
 news:a6268ff50d58cb92d952e5b612 news.digitalmars.com...

 Hello Nick,


 "BCS" <none anon.com> wrote in message
 news:a6268ff50558cb92691721562e news.digitalmars.com...


 yah, for some programs you rarely want to close the program but often
 want to close the UI.






 It can be, OTOH I might want the UI process killed without killing the
 main program. Another point is the other side of the assertion, "you
 rarely want to close the program" as in 90% of the time even when I hit
 the x button, I don't actually want to close the program.



 The whole point of the 'x' button is the close the program. Always has  
 been.
 If I didn't want to close the program, I wouldn't push it. If you want to
 hide/kill the UI without closing the program, that's "minimize". True,
 minimizing to the taskbar doesn't kill the UI process/thread (assuming it
 even is a separate process/thread), but in the rare cases where the
 distinction of "UI process running/killed" actually matters, the program  
 can
 still do that through a minimize to tray. And while neither "minimize"  
 nor
 "close" truly mean "minimize to tray", clearly "minimize" is FAR closer  
 in
 both wording and behavior. Any way you look at it, having a "close"  
 button
 that doesn't "close" the app is like having a "cancel" button that  
 prints,
 or a "save" button that plays music.



Yahoo messenger's X button behavior:

click on it -> "Although the main window has been closed, Yahoo! Messenger  
will continue to run in the system tray..."

With a checkbox that says "Show this message in the future."

That's perfect for me.  YM also has an option to automatically remove the  
taskbar button when minimized (so minimized does the behavior you want it  
to do).

-Steve
Apr 24 2009
prev sibling parent "Denis Koroskin" <2korden gmail.com> writes:
On Fri, 24 Apr 2009 13:54:26 +0400, Nick Sabalausky <a a.a> wrote:


 "BCS" <none anon.com> wrote in message
 news:a6268ff50558cb92691721562e news.digitalmars.com...

 Hello Christopher,


 Nick Sabalausky wrote:


 The absolute worst of all though is when an app (*cough* skype
 *cough*) decides that "close" and "the 'close' button" should mean
 "don't close anything at all, but minimize to tray instead". That
 should be a firing squad offense ;)



 pretty much expect it of any application that's meant to be running
 for a long time and only rarely needing user interaction (such as a
 bittorrent client).



 yah, for some programs you rarely want to close the program but often  
 want
 to close the UI.



 That's called "Minimize".



"Minimize" button usually minimizes the window to task bar.

Some applications provide an additional button alongside minimize and close
that minimizes to tray (Emule and others).
Some other applications minimize to tray when you hold Shift while clicking the
minimize button - Vypress chat, Download Master, Total Commander (plugin) and
others. But overall - it's very inconsistent.

I personally wish that more programs adopt Shift+Minimize -> Tray behavior,
it's easy to remember and easy to implement.
Apr 24 2009
prev sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Nick Sabalausky wrote:

 "Steven Schveighoffer" <schveiguy yahoo.com> wrote in message 
 news:op.usux6bskeav7ka steves.networkengines.com...

 I was never a huge fan of application themes.  I don't mind a theme for 
 the whole system (as long as it's simple), but I don't want iTunes to look 
 different just because it can.



 That's one of my biggest pet peeves about modern software. I can't really do 
 the subject justice without delving into a giant pile of expletives. 



It took me some serious browsing before I found a non-obtrusive skin for 
gmplayer. And I hated to have to do that. It should have been the default.


 But worse still is when they decide to go and piss all over not just standard 
 looks, but also standard behaviors. Like how the Win build of iTunes will 
 still ignore/"eat" any click that brings it to the foreground. If I wanted 
 that behavior I'd be running a Mac.



That's a good thing with many *nix GUIs. You can have several 
overlapping windows, and even do stuff in the non-top ones. But they 
really should respect the target GUIs way of doing things, when porting.


 The absolute worst of all though is when an app (*cough* skype *cough*) 
 decides that "close" and "the 'close' button" should mean "don't close 
 anything at all, but minimize to tray instead". That should be a firing 
 squad offense ;) Joking aside though, any of these are guaranteed ways to 
 make me lose any and all respect for a piece of software and its developers, 
 especially if they're arrogant enough to provide no way to turn such things 
 off.



Yeah, the biggest motivation (next to being graphical per se) for GUIs 
was uniform app behavior. That way you only would need to learn the 
common basics, and then, ostensibly, you could use any new app right off 
the bat. (In the bad old days, you really had to learn to use every app, 
one at a time.)
Apr 24 2009
parent reply grauzone <none example.net> writes:
 It took me some serious browsing before I found a non-obtrusive skin for 
 gmplayer. And I hated to have to do that. It should have been the default.




AFAIK, the gmplayer GUI is deprecated. Use mplayer or smplayer. smplayer 
is a GUI for mplayer that surprisingly manages to use a standard GUI, 
and not some skinable specially-made media GUI bullshit, that plagues 
most media players.
Apr 24 2009
parent Georg Wrede <georg.wrede iki.fi> writes:
grauzone wrote:

 It took me some serious browsing before I found a non-obtrusive skin 
 for gmplayer. And I hated to have to do that. It should have been the 
 default.



 AFAIK, the gmplayer GUI is deprecated. Use mplayer or smplayer. smplayer 
 is a GUI for mplayer that surprisingly manages to use a standard GUI, 
 and not some skinable specially-made media GUI bullshit, that plagues 
 most media players.



Thanks!
Apr 24 2009
prev sibling next sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 14:32:13 -0400, Georg Wrede <georg.wrede iki.fi> wrote:

 I mean, who's such a nutcase that he forgets halfway in the dragging, 
 what it is he's dragging?



 It might be useful if you accidentally start dragging the wrong thing, 
 and then realize because you are dragging the wrong picture/text/etc.
 
 But my point was really: you complained that you couldn't see the target 
 because the picture is covering it.  My experience is that I can clearly 
 see the target because the picture is translucent (I can see the target 
 "underneath" the picture).




My complaint was about doing stuff just because you can. The dragging 
was just the first gross example that crossed my mind.

(I'm on a slow graphics card. Besides, it hasn't bothered me enough to 
start investigating. Heck, for all I know, I could configure it away.)
Apr 24 2009
parent "Nick Sabalausky" <a a.a> writes:
"Georg Wrede" <georg.wrede iki.fi> wrote in message 
news:gsrqbj$iu1$1 digitalmars.com...

 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 14:32:13 -0400, Georg Wrede <georg.wrede iki.fi> 
 wrote:

 I mean, who's such a nutcase that he forgets halfway in the dragging, 
 what it is he's dragging?



 It might be useful if you accidentally start dragging the wrong thing, 
 and then realize because you are dragging the wrong picture/text/etc.

 But my point was really: you complained that you couldn't see the target 
 because the picture is covering it.  My experience is that I can clearly 
 see the target because the picture is translucent (I can see the target 
 "underneath" the picture).




 My complaint was about doing stuff just because you can. The dragging was 
 just the first gross example that crossed my mind.

 (I'm on a slow graphics card. Besides, it hasn't bothered me enough to 
 start investigating. Heck, for all I know, I could configure it away.)



When I try to drag a group of files in Windows Explorer it makes them 
translucent instead of opaque. But I *still* find it unforgivably difficult 
to see underneath to where I'm dropping them. (Although maybe I can turn 
that off...)
Apr 24 2009
prev sibling next sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Jarrett Billingsley wrote:

 On Thu, Apr 23, 2009 at 2:32 PM, Georg Wrede <georg.wrede iki.fi> wrote:
 

 (OT: an excellent example of this It's Done Because We Noticed We Could
 stuff is in Firefox. When a picture is a link to another page, and you want
 to drag that to the tab area, the entire picture is dragged with the mouse.
 Now, how the hell am I supposed to hit the small tab area when the large
 picture covers half of my Firefox??






 cubicle, etc. But there should be some obvious or useful *purpose* for
 dragging entire pictures where a mouse pointer would be clearer, cleaner,
 easier for the user, and use less computer cycles.

 I mean, who's such a nutcase that he forgets halfway in the dragging, what
 it is he's dragging?



 Middle-click.



Yeah.

But I still don't see the glamouros advantages in dragging whole pictures.

And I often drag stuff to existing tabs. A good example is when browsing 
http://apod.nasa.gov/apod/ap090424.html where I usually end up with a 
dozen tabs in no time.
Apr 24 2009
parent Benji Smith <dlanguage benjismith.net> writes:
Georg Wrede wrote:

 Jarrett Billingsley wrote:

 I mean, who's such a nutcase that he forgets halfway in the dragging, 
 what
 it is he's dragging?



 Middle-click.



 Yeah.
 
 But I still don't see the glamouros advantages in dragging whole pictures.
 
 And I often drag stuff to existing tabs. A good example is when browsing 
 http://apod.nasa.gov/apod/ap090424.html where I usually end up with a 
 dozen tabs in no time.



I think it's because Firefox doesn't know you're just dragging those 
images to a tab. For all the browser knows, you're playing a game of 
chess, and you're dragging a pawn to E5. In which case, it makes a lot 
of sense for a ghost image to follow the drag behavior.

For generalized dragdrop, I think ghosted images are a good, safe guess.

Did you know you can right-click to "Open in New Tab"?

--benji
Apr 27 2009
prev sibling parent reply Georg Wrede <georg.wrede iki.fi> writes:
Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 14:32:13 -0400, Georg Wrede <georg.wrede iki.fi> wrote:

 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 12:09:20 -0400, Georg Wrede <georg.wrede iki.fi> 

 So now I have to learn to remember to grab bigger pictures near some 
 edge. And I really can't see *any* valid benefit for having to drag 
 the picture. I'd rather have it the old way, where the mouse pointer 
 simply changes shape, so you know you're dragging. Damn, damn...)



 image, so I can still see where my mouse pointer is aimed.  Maybe you 
 don't have enough colors enabled on your screen?



 Sure it looks good, and the computer owner can brag to the guy in the 
 next cubicle, etc. But there should be some obvious or useful 
 *purpose* for dragging entire pictures where a mouse pointer would be 
 clearer, cleaner, easier for the user, and use less computer cycles.

 I mean, who's such a nutcase that he forgets halfway in the dragging, 
 what it is he's dragging?



 One thing that does annoy me is if you are doing this over a slow RDP 
 link, the eye candy isn't worth it.
 
 I was never a huge fan of application themes.  I don't mind a theme for 
 the whole system (as long as it's simple), but I don't want iTunes to 
 look different just because it can.  I think it has been discussed 
 before that most video editors have the slickest GUI, with real-looking 
 knobs and "led's", but the video editing part of it is buggy as hell.



You're the first one to comment on the actual issue!!! :-)

Those video editors, iTunes and such look like they're programmed by 
12-year olds. Somewhere there should be an adult saying what not to do!

I bet the guy who did this never expected that whole-picture dragging 
actually uses more electricity in your computer. When every Firefox user 
(and the others "who have to implement this too, so as not to look 
inferior!") in the whole world drags whole pictures, the combined 
increase in world electric usage rises well above his day-job salary.

Greenpeace ought to shoot him.
Apr 24 2009
parent reply "Nick Sabalausky" <a a.a> writes:
"Georg Wrede" <georg.wrede iki.fi> wrote in message 
news:gsrrfn$kv3$1 digitalmars.com...

 Those video editors, iTunes and such look like they're programmed by 
 12-year olds. Somewhere there should be an adult saying what not to do!



Well put.


 I bet the guy who did this never expected that whole-picture dragging 
 actually uses more electricity in your computer. When every Firefox user 
 (and the others "who have to implement this too, so as not to look 
 inferior!") in the whole world drags whole pictures, the combined increase 
 in world electric usage rises well above his day-job salary.

 Greenpeace ought to shoot him.



Funny, earlier today I was just thinking very much the same thing about a 
video I saw a few weeks ago of Palm's WebOS (Or it might have been some 
clone of WebOS). Fancy moving curves and scaling icons that serve absolutely 
no purpose besides 1. "flash for the sake of flash" (I *hate* that!) and 2. 
drain the battery. Which is really sad, I used to have so much respect for 
Palm...But then they killed graffiti, and then replaced their PDAs with cell 
phones (and we never did get PDAs with hard drives, which is ridiculous, 
even my portable music player has a damn hard drive, which of course is one 
device I wouldn't even need if my PDA *had a hdd!!*), and now this WebOS 
garbage, sheesh...And speaking of PDAs, now Nintendo's been changing their 
DS from a reasonable gaming device into the world's shittiest PDA...Man, the 
world of software and consumer electronics really depresses me these days...
Apr 24 2009
parent Georg Wrede <georg.wrede iki.fi> writes:
Nick Sabalausky wrote:

 "Georg Wrede" <georg.wrede iki.fi> wrote in message 
 news:gsrrfn$kv3$1 digitalmars.com...

 Those video editors, iTunes and such look like they're programmed by 
 12-year olds. Somewhere there should be an adult saying what not to do!



 Well put.
 

 I bet the guy who did this never expected that whole-picture dragging 
 actually uses more electricity in your computer. When every Firefox user 
 (and the others "who have to implement this too, so as not to look 
 inferior!") in the whole world drags whole pictures, the combined increase 
 in world electric usage rises well above his day-job salary.

 Greenpeace ought to shoot him.



 Funny, earlier today I was just thinking very much the same thing about a 
 video I saw a few weeks ago of Palm's WebOS (Or it might have been some 
 clone of WebOS). Fancy moving curves and scaling icons that serve absolutely 
 no purpose besides 1. "flash for the sake of flash" (I *hate* that!) and 2. 
 drain the battery. Which is really sad, I used to have so much respect for 
 Palm...But then they killed graffiti, and then replaced their PDAs with cell 
 phones (and we never did get PDAs with hard drives, which is ridiculous, 
 even my portable music player has a damn hard drive, which of course is one 
 device I wouldn't even need if my PDA *had a hdd!!*), and now this WebOS 
 garbage, sheesh...And speaking of PDAs, now Nintendo's been changing their 
 DS from a reasonable gaming device into the world's shittiest PDA...Man, the 
 world of software and consumer electronics really depresses me these days... 



It was different in the old days. In 1981 HP introduced the HP-12c 
financial calculator. Seems it's still sold, for about $60.

I'd like to see the consumer gadget introduced this year, that is still 
sold in 2037.

And they're built to last. I have a few HP calculators (the earliest a 
HP-25, I bought in 1975), and they're fiercely usable, sturdy, and 
definitely not cluttered with unneeded "features". I still use them, 
particularly the HP-28s, the HP-25, and the HP-95 (which is actually an 
IBM PC in palmtop size).
Apr 24 2009
prev sibling parent Jarrett Billingsley <jarrett.billingsley gmail.com> writes:
On Thu, Apr 23, 2009 at 2:32 PM, Georg Wrede <georg.wrede iki.fi> wrote:


 (OT: an excellent example of this It's Done Because We Noticed We Could
 stuff is in Firefox. When a picture is a link to another page, and you want
 to drag that to the tab area, the entire picture is dragged with the mouse.
 Now, how the hell am I supposed to hit the small tab area when the large
 picture covers half of my Firefox??






 Sure it looks good, and the computer owner can brag to the guy in the next
 cubicle, etc. But there should be some obvious or useful *purpose* for
 dragging entire pictures where a mouse pointer would be clearer, cleaner,
 easier for the user, and use less computer cycles.

 I mean, who's such a nutcase that he forgets halfway in the dragging, what
 it is he's dragging?



Middle-click.
Apr 23 2009
prev sibling next sibling parent "Denis Koroskin" <2korden gmail.com> writes:
On Thu, 23 Apr 2009 17:35:59 +0400, Frits van Bommel
<fvbommel remwovexcapss.nl> wrote:


 Denis Koroskin wrote:

 On Thu, 23 Apr 2009 16:20:03 +0400, Don <nospam nospam.com> wrote:


 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
     foreach(x; a) sink(x);
     sink(b);
     sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all your   
 strings in, even if there are 200 million of them and your giant  
 string  is just going to be written to a file anyway.



 suggested the following design (but can't find my post anymore):
  A signature of toString() should be as follows:
  char[] toString(string format = null, char[] buffer = null);
  Bonuses you get from that:
 You don't have to change your code (aside from toString() returning  
 mutable array now, but it is very easy to fix)
 It allows you to avoid allocations - just pass a temporary buffer to  
 use!



 It'll still allocate if the buffer isn't big enough.



Of course, it allows you to avoid allocations, but it doesn't necessarily
eliminate them.


 I usually define something like "void streamTo(Sink sink)" in a base  
 class if I want non-allocating output. Adding a format string to the  
 parameter list should be easy, but I haven't needed it yet.
 I then usually implement toString by passing an appending Sink to that  
 method, just so Tango's formatting methods will be able to use it.



 IMHO It'd be pretty nice for the standard formatting systems (both the  
 Tango and Phobos ones) to just call a standard Object method taking  
 (Sink sink, char[] format = null) on objects.



Sink is okay, but most my usages belong to one of the two scenarios:
1) I need a string representation of an Object - how is Sink useful here? I
just want to call obj.toString() and get the result
2) I need to print it to stdout, thus I call writeln/Stdout(obj); - Sink is of
no use here again.

That said, I have other use-cases, too, but never once I needed a custom Sink
property.
Besides, having a Sink object is redundant and makes things more complex in
most cases. Compare:

class Number
{
    private int _number;

    // My version
    char[] toString(string format, char[] buffer = null) {
        return std.string.format(buffer, format, _number); // use default
formatter, buffer is provided to avoid allocations
    }

    // Your version
    void toString(Sink sink, string format = null) {
        // what should I do here? How do I avoid allocations? I have to
duplicate code anyway
        char[16] buffer;
        buffer = std.string.format(buffer, format, _number);
        sink(buffer);
    }
}

How is that better than using external sink? Use composition!
toString/streamOut can be implemented on top of my toString:

char[] buffer;
sink(object.toString(format, buffer)); // I believe explicit is better here

Also, this way sink is called directly an may be inlined.

Besides, why is it called toString(), if it doesn't give me an object's string
representation???


 Backward compatibility might be tricky though, if you want to support  
 both overriding and calling of toString(). (You can't have the default  
 toString implementation call the format function *and* have the default  
 format function implementation call toString)



My version is (almost) backwards compatible.
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 10:30:15 -0400, Andrei Alexandrescu  
<SeeWebsiteForEmail erdani.org> wrote:


 Daniel Keep wrote:

  Andrei Alexandrescu wrote:

 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 09:24:59 -0400, Andrei Alexandrescu
 <SeeWebsiteForEmail erdani.org> wrote:


 Steven Schveighoffer wrote:

 This has to go into object.d and be part of the runtime, where
 std.range doesn't exist.  There is nothing stopping you from  
 calling:
  streamOut(&outputrange.put);
  So I'd rather have a sink function.



 support put() so it integrates with statically-bound output ranges.

 interface OutRange
 {
      void put(... a number of overloads ...);
 }



 anyways).  That interface has to go in the runtime, though.

 We may not be able to do this using templates... it has to be a
 virtual function in Object to be on-par with toString.  This means
 struct interfaces are a requirement if you want to use ranges :(



 implicit interface using .put against a struct will work just as well
 with templates. (The template doesn't care whether obj.put(x) is a
 virtual call or statically-bound call.)

 Andrei



 virtual
 function in Object to be on-par with toString."
  Note that toString is a virtual method.  You are proposing replacing
 toString with a template.  You cannot have virtual template methods.
 Ergo, "new toString" would be inaccessible without the actual type, and
 certainly not at runtime.



 The toStream that I have in mind is virtual and takes an interface of  
 type OutRange as outlined above.



OK, that's fine, I was working off your original proposal:

void streamOut(R)(R range)
{
      foreach(x; a) range.put(x);
      range.put(b);
      range.put(c);
}

Of course, this then eliminates structs from being OutRange's without  
having struct interfaces.  As most ranges are structs (and rightfully so,  
who wants to call 3 virtual functions every loop!), they would have to be  
wrapped under the current compiler. Or am I missing something else?

-Steve
Apr 23 2009
prev sibling next sibling parent "Denis Koroskin" <2korden gmail.com> writes:
On Thu, 23 Apr 2009 18:28:53 +0400, Andrei Alexandrescu
<SeeWebsiteForEmail erdani.org> wrote:


 Denis Koroskin wrote:

 Sink is okay, but most my usages belong to one of the two scenarios: 1)  
 I need a string representation of an Object - how is Sink useful
 here? I just want to call obj.toString() and get the result 2) I need
 to print it to stdout, thus I call writeln/Stdout(obj); - Sink is of
 no use here again.



 I hear you, but there are quite a few more considerations that apply.

 For one, making string the common format of all objects is pretty  
 hamfisted. We need to integrate things like binary streams too. Second,  
 using string append and composing with it is bound to be inefficient,  
 and for multiple reasons. You can't just say that a reasonable way to  
 print a matrix is to call toString against it and print the resulting  
 string. With the temporary buffer passed-in or not, that's just a  
 terrible design.

 But you need not fear. Converting to string will remain easy and simple,  
   it will only be a particular case of streaming objects out.


 Andrei



I'm fine with that, especially if entire Phobos will be consistent with it
(e.g. std.string.format accepts sink object etc). There a few problems with it,
though.

I like the "toStream" name but I believe it is a bit misleading - if toString()
returns a string, then toStream() should return stream, too, not accept it.

But what about custom formatting? Previously I stated that current scheme
doesn't allow them, but it turned out to be possible.

For example, you introduced custom array formatting:

%(s; ) -> array.toString("s; ", ...);

Similar approach may be used for other user-defined formatting options:

%s -> obj.toString("s");
%d -> obj.toString("d");
...
%(any_set_of_characters) -> obj.toString("any_set_of_characters"); // including
inner %() etc


Example: given an array of arrays of ints, print them as follows: "[ [1, 2, 3,
4, ]; [5, 6, 7, 8, ]; [9, a, b, c, ]; ]"

int[][] arrayOfArraysOfInts;
writefln("[ %([%(x, )]; )]", arrayOfArraysOfInts);

Just to make it more clear:

[ %([%(x, )]; )] -> "[ " ~ arrayOfArraysOfInts.toString("[%(x, )]; ") ~ "]"
Apr 23 2009
prev sibling next sibling parent "Denis Koroskin" <2korden gmail.com> writes:
On Thu, 23 Apr 2009 19:34:38 +0400, Don <nospam nospam.com> wrote:


 Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 Georg Wrede wrote:

 Don wrote:

 bearophile wrote:

 This post is mostly for Andrei.
 I have played with D2 a bit; probably I'll need months to digest  
 it and its new Phobos2. While I explore Phobos I'll probably post  
 some comments/bugs around here.

 After reading this:
 http://blogs.msdn.com/vcblog/archive/2009/04/22/decltype-c-0x-features
in-vc10-part-3.aspx  
 I have tried to write a toy implementation of it in D2 (not using  
 Phobos2 yet):

 import std.stdio: writeln;
 import std.string: format;

 struct Watts {








 Two things to improve:
 1) All structs must have a default built-in opString, a good  
 representation can be:
 StructName(field_value1, field_value2, field_value1, ...).
 It's not a perfect textual representation, but it's WAY better  
 than the current one (currently it shows just the struct name).
 (Printing the module name before the struct name is bad, most  
 times is just noise)



 No!
 <rant>
 toString() is one of the most dreadful features in D. Trying to  
 slightly improve it is a waste of time -- the whole concept needs  
 to be redone.
 It's horribly inflexible, tedious, and hugely inefficient. What  
 more could there be to hate?

 - the object being called has no context. It doesn't know what  
 format is desired, for example.
 - you can't emulate formatting of built-in types, NOT EVEN int!  
 You can't do left-align, pad with zeros, include + sign, display  
 in hex.

 - it's got no stream concept. Every object has to create and  
 manage its own buffer, and nobody knows if anyone actually needs  
 it.

 It ought to be at least as simple as:

 struct Foo(A, B, C){
 A[10] a;
 B b;
 C c;
 void toString(Sink sink){
    foreach(x; a) sink(x);
    sink(b);
    sink(c);
 }
 }
 ... but it's not, you have to create a silly buffer to put all  
 your strings in, even if there are 200 million of them and your  
 giant string is just going to be written to a file anyway.

 I'd like to see version(debug) {} put around Object.toString().  
 It's a deathtrap feature that's got no business being used other  
 than for debugging.
 </rant>



 First of all, printing stuff "struct.toString()" style is for two  
 things:

  o  Debugging
  o  Small throwaway code snippets

 The latter mainly being for two purposes:

  o  Testing quick concepts, trying out library functions, etc.
  o  For the newbie, when he's learning D, but not output formatting.

 No "Real Program" uses this, because there you typically do proper  
 formatting of the output anyway, and almost never print entire  
 structs or objects as such. Instead, rather the information that  
 they represent.



 How about something like BigInt? Why can't you just print it out?



 ?? Why couldn't you?

 They're not stored as strings (not Janice's anyway), but I don't  
 understand the question.



 You can write:

 int a, b;
 a=10; b=20;
 writefln("%d %x", a, b);

 I'd like to be able to write:

 BigInt a, b;
 a=10; b=20;
 writefln("%d %x", a, b);

 and have it behave exactly the same.



 automated. (For the small/debugging purpose.)
  Andrei seems to be at this, but right now I don't know enough details  
 to say anything. It seems to be an even bigger thing than what I  
 suggested, and knowing he does things in a universal way, one would  
 assume that if a class "wants" to be printed in some way, then maybe  
 there'll be some provisions for it.
  But, things like BigInt, that really are classes or structs that have  
 to be printed in a specific way, I have a hard time figuring out how to  
 printe them using write_f_ln.
  One way would be to have the format specification (as in "%x") be  
 somehow passed to the toString of the struct/class. Then the class  
 could decide for itself how to be printed in this case.
   But even this is stretching it a bit, since some more complicated  
 class/struct might need a more elaborate hint than just one letter. And  
 by that time the whole thing starts to crumble, in usability issues, at  
 least.
  One thing we sholuld be wary of is overdesign. BigInt is ok, but by  
 the time we try to include a class called  
 CompleteSimulationOfAnF1RaceCar, we're screwed. :-)  I see no way to  
 incorporate them into writefln or even plain writeln. Or at least, no  
 *use*.



 I think it'd be reasonable to limit things to the options available for  
 built-in types. Outside of that, custom formatting functions make a lot  
 of sense. The problem is that toString() _looks_ like it emulates  
 built-in formatting, but it only does '%s'. So it's really beguiling.

 BTW, when passing the output to a sink, it should be possible to (say)  
 format your members with '%x' format, but you can't do that by  
 permanently altering sink: it should revert to its previous value once  
 you've sunk your last member. (I think this C++ iostreams got this  
 wrong).



I'm not sure Sink should know anything about formatting. It's up to class
designer to decide what custom formatters mean - they may be *very* complex.
See my other post about formatting.
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 12:09:20 -0400, Georg Wrede <georg.wrede iki.fi> wrote:


 (OT: an excellent example of this It's Done Because We Noticed We Could  
 stuff is in Firefox. When a picture is a link to another page, and you  
 want to drag that to the tab area, the entire picture is dragged with  
 the mouse. Now, how the hell am I supposed to hit the small tab area  
 when the large picture covers half of my Firefox??

 So now I have to learn to remember to grab bigger pictures near some  
 edge. And I really can't see *any* valid benefit for having to drag the  
 picture. I'd rather have it the old way, where the mouse pointer simply  
 changes shape, so you know you're dragging. Damn, damn...)



On my system, dragging the image drags a translucent copy of the image, so  
I can still see where my mouse pointer is aimed.  Maybe you don't have  
enough colors enabled on your screen?

-Steve
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 14:32:13 -0400, Georg Wrede <georg.wrede iki.fi> wrote:


 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 12:09:20 -0400, Georg Wrede <georg.wrede iki.fi>  
 wrote:


 (OT: an excellent example of this It's Done Because We Noticed We  
 Could stuff is in Firefox. When a picture is a link to another page,  
 and you want to drag that to the tab area, the entire picture is  
 dragged with the mouse. Now, how the hell am I supposed to hit the  
 small tab area when the large picture covers half of my Firefox??

 So now I have to learn to remember to grab bigger pictures near some  
 edge. And I really can't see *any* valid benefit for having to drag  
 the picture. I'd rather have it the old way, where the mouse pointer  
 simply changes shape, so you know you're dragging. Damn, damn...)



 image, so I can still see where my mouse pointer is aimed.  Maybe you  
 don't have enough colors enabled on your screen?



 Sure it looks good, and the computer owner can brag to the guy in the  
 next cubicle, etc. But there should be some obvious or useful *purpose*  
 for dragging entire pictures where a mouse pointer would be clearer,  
 cleaner, easier for the user, and use less computer cycles.

 I mean, who's such a nutcase that he forgets halfway in the dragging,  
 what it is he's dragging?



It might be useful if you accidentally start dragging the wrong thing, and  
then realize because you are dragging the wrong picture/text/etc.

But my point was really: you complained that you couldn't see the target  
because the picture is covering it.  My experience is that I can clearly  
see the target because the picture is translucent (I can see the target  
"underneath" the picture).

-Steve
Apr 23 2009
prev sibling next sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Thu, 23 Apr 2009 14:32:13 -0400, Georg Wrede <georg.wrede iki.fi> wrote:


 Steven Schveighoffer wrote:

 On Thu, 23 Apr 2009 12:09:20 -0400, Georg Wrede <georg.wrede iki.fi>  
 wrote:


 (OT: an excellent example of this It's Done Because We Noticed We  
 Could stuff is in Firefox. When a picture is a link to another page,  
 and you want to drag that to the tab area, the entire picture is  
 dragged with the mouse. Now, how the hell am I supposed to hit the  
 small tab area when the large picture covers half of my Firefox??

 So now I have to learn to remember to grab bigger pictures near some  
 edge. And I really can't see *any* valid benefit for having to drag  
 the picture. I'd rather have it the old way, where the mouse pointer  
 simply changes shape, so you know you're dragging. Damn, damn...)



 image, so I can still see where my mouse pointer is aimed.  Maybe you  
 don't have enough colors enabled on your screen?



 Sure it looks good, and the computer owner can brag to the guy in the  
 next cubicle, etc. But there should be some obvious or useful *purpose*  
 for dragging entire pictures where a mouse pointer would be clearer,  
 cleaner, easier for the user, and use less computer cycles.

 I mean, who's such a nutcase that he forgets halfway in the dragging,  
 what it is he's dragging?



One thing that does annoy me is if you are doing this over a slow RDP  
link, the eye candy isn't worth it.

I was never a huge fan of application themes.  I don't mind a theme for  
the whole system (as long as it's simple), but I don't want iTunes to look  
different just because it can.  I think it has been discussed before that  
most video editors have the slickest GUI, with real-looking knobs and  
"led's", but the video editing part of it is buggy as hell.

-Steve
Apr 23 2009
prev sibling next sibling parent Jarrett Billingsley <jarrett.billingsley gmail.com> writes:
On Thu, Apr 23, 2009 at 6:01 PM, Christopher Wright <dhasenan gmail.com> wr=
ote:

 Andrei Alexandrescu wrote:

 Yes. The way it should be is not with sink, but with the standard output
 iterator method put().

 void streamOut(T, R)(T object, R range)
 {
 =A0 =A0foreach(x; a) range.put(x);
 =A0 =A0range.put(b);
 =A0 =A0range.put(c);
 }



 // object.d
 class Object
 {
 =A0 =A0 =A0 =A0void streamOut(R)(R range);
 }

 No?



No.  Templated methods are not virtual.
Apr 23 2009
prev sibling next sibling parent Jesse Phillips <jessekphillips gmail.com> writes:
On Thu, 23 Apr 2009 21:40:36 -0400, Christopher Wright wrote:


 Nick Sabalausky wrote:

 "Steven Schveighoffer" <schveiguy yahoo.com> wrote in message
 news:op.usux6bskeav7ka steves.networkengines.com...

 I was never a huge fan of application themes.  I don't mind a theme
 for the whole system (as long as it's simple), but I don't want iTunes
 to look different just because it can.



 really do the subject justice without delving into a giant pile of
 expletives. But worse still is when they decide to go and piss all over
 not just standard looks, but also standard behaviors. Like how the Win
 build of iTunes will still ignore/"eat" any click that brings it to the
 foreground. If I wanted that behavior I'd be running a Mac.
 
 The absolute worst of all though is when an app (*cough* skype *cough*)
 decides that "close" and "the 'close' button" should mean "don't close
 anything at all, but minimize to tray instead". That should be a firing
 squad offense ;)



 I'd be killing my IM client constantly if not for that feature. I pretty
 much expect it of any application that's meant to be running for a long
 time and only rarely needing user interaction (such as a bittorrent
 client).



I think he was referring to not having an exit. That is File->Exit is 
also minimize to tray which is not the case in most such apps.
Apr 23 2009
prev sibling parent "Simen Kjaeraas" <simen.kjaras gmail.com> writes:
grauzone wrote:


 void streamOut(T, R)(T object, R range)
 {
     foreach(x; a) range.put(x);
     range.put(b);
     range.put(c);
 }















 So, um... what is a b c and T object?



In my opinion, this is a confusing example. I believe it was meant to be:

void streamOut(T, R)(T object, R range)
{
  foreach(x; object.a) range.put(x);
  range.put(object.b);
  range.put(object.c);
}

So, streamOut is a free function, which it normally would not be. Now, consider
this:

struct foo {
  int[] a;
  bool b;
  char c;

  void streamOut(R)(R range) {
    foreach(x; a) range.put(x);
    range.put(b);
    range.put(c);
  }
}

I believe this is what you'd normally do.

Do note that I might have misinterpreted it all, as Andrei's code would not do
what I have outlined above, I only feel it makes the most sense.

--
  Simen
Apr 24 2009