digitalmars.D - foreach_reverse is better than ever

Gone, that is. Walter agreed to remove it.

To achieve the functionality of

foreach_reverse (r) { ... }

use

foreach (retro(r)) { ... }

using retro in std.range.


Andrei

Feb 13 2010

Jonathan M Davis <jmdavisProg gmail.com> writes:

Andrei Alexandrescu wrote:

 Gone, that is. Walter agreed to remove it.
 
 To achieve the functionality of
 
 foreach_reverse (r) { ... }
 
 use
 
 foreach (retro(r)) { ... }
 
 using retro in std.range.
 
 
 Andrei


I assume that this was to get rid of a keyword and reduce duplicate 
functionality.

Though I must say that I find retro to be a bit funny. I would have expected 
it to be reverse. It would be clearer, I think, but it's not like it's hard 
to find out what retro does and remember it.

- Jonathan M Davis

Feb 14 2010

Jacob Carlborg <doob me.com> writes:

On 2/14/10 09:14, Jonathan M Davis wrote:
 Andrei Alexandrescu wrote:

 Gone, that is. Walter agreed to remove it.

 To achieve the functionality of

 foreach_reverse (r) { ... }

 use

 foreach (retro(r)) { ... }

 using retro in std.range.


 Andrei


 I assume that this was to get rid of a keyword and reduce duplicate
 functionality.

 Though I must say that I find retro to be a bit funny. I would have expected
 it to be reverse. It would be clearer, I think, but it's not like it's hard
 to find out what retro does and remember it.

 - Jonathan M Davis


It iterates backwards, all the way back to the 50s. I think "reverse" is 
a much better word.


/Jacob Carlborg

Feb 14 2010

Michel Fortin <michel.fortin michelf.com> writes:

On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think "reverse" 
 is a much better word.


Agree.

My dictionary says: "retro": imitative of a style, fashion, or design 
from the recent past.

It's an amusing name in the way Andrei likes it, but the meaning isn't 
very clear. "reverse" would be a better name.

-- 
Michel Fortin
michel.fortin michelf.com
http://michelf.com/

Feb 14 2010

bearophile <bearophileHUGS lycos.com> writes:

Michel Fortin:
 It's an amusing name in the way Andrei likes it, but the meaning isn't 
 very clear. "reverse" would be a better name.


In Python it's "reversed":

 a = [5,7,1,3]
 reversed(a)






 list(reversed(a))







Python use verbs in past tense (like "sorted", "reversed", etc) to denote
something that doesn't change the given input (while "sort" sorts in-place).

Bye,
bearophile

Feb 14 2010

Michel Fortin <michel.fortin michelf.com> writes:

On 2010-02-14 09:34:16 -0500, bearophile <bearophileHUGS lycos.com> said:

 Python use verbs in past tense (like "sorted", "reversed", etc) to 
 denote something that doesn't change the given input (while "sort" 
 sorts in-place).


That certainly is a useful convention to make things easier to read. 
I'd very much like to see it used in D.


-- 
Michel Fortin
michel.fortin michelf.com
http://michelf.com/

Feb 14 2010

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


At least in this case being funny was not the point. I needed a name 
that was (a) short, (b) different from "reverse", (c) memorable. It is 
understood that other paint colors are available, but please don't 
forget to give a little love to the painter. :o) It would be of course 
best if names that arguably hurt the language were changed, so please 
compile a list.

Andrei

Feb 14 2010

Mike James <foo bar.com> writes:

Andrei Alexandrescu Wrote:

 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name 
 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.
 
 Andrei


1.   Contrawise
2.   Rearward
3.   AssBackwards
4.   Reorientated
5.   Turnedabout
6.   Turnedaround
7.   Inversified
8.   Flipped
9.   Refluxed
10. VolteFace

or how about Reverse...

-=mike=-

Feb 14 2010

bearophile <bearophileHUGS lycos.com> writes:

Mike James:
 1.   Contrawise
 2.   Rearward
 3.   AssBackwards
 4.   Reorientated
 5.   Turnedabout
 6.   Turnedaround
 7.   Inversified
 8.   Flipped
 9.   Refluxed
 10. VolteFace
 
 or how about Reverse...


Wonderful, I elect you the official namer for Phobos :-)
And I think Andrei meant a list of all the bad names in Phobos :-)
What about "reversed"? :-)

Bye,
bearophile

Feb 14 2010

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

bearophile wrote:
 Mike James:
 1.   Contrawise
 2.   Rearward
 3.   AssBackwards
 4.   Reorientated
 5.   Turnedabout
 6.   Turnedaround
 7.   Inversified
 8.   Flipped
 9.   Refluxed
 10. VolteFace

 or how about Reverse...


 Wonderful, I elect you the official namer for Phobos :-)
 And I think Andrei meant a list of all the bad names in Phobos :-)
 What about "reversed"? :-)


I don't mind "reversed" but it's longer than "retro" and the convention 
doesn't scale. For example, both active and passive forms of "split" 
look the same.

Andrei

Feb 14 2010

bearophile <bearophileHUGS lycos.com> writes:

Andrei Alexandrescu:
 I don't mind "reversed" but it's longer than "retro" and the convention 
 doesn't scale. For example, both active and passive forms of "split" 
 look the same.


For me "retro" is acceptable. I don't love "iota" but I can accept it too.
Other names of Phobos2 can be improved.

Bye,
bearophile

Feb 14 2010

Justin Johansson <no spam.com> writes:

bearophile wrote:
 Andrei Alexandrescu:
 I don't mind "reversed" but it's longer than "retro" and the convention 
 doesn't scale. For example, both active and passive forms of "split" 
 look the same.


 For me "retro" is acceptable. I don't love "iota" but I can accept it too.
Other names of Phobos2 can be improved.
 
 Bye,
 bearophile


Go language has "iota" so it's gotta be goodness :-)

Feb 14 2010

"Nick Sabalausky" <a a.a> writes:

"bearophile" <bearophileHUGS lycos.com> wrote in message 
news:hl9ipc$26r1$1 digitalmars.com...
 Andrei Alexandrescu:
 I don't mind "reversed" but it's longer than "retro" and the convention
 doesn't scale. For example, both active and passive forms of "split"
 look the same.


 For me "retro" is acceptable. I don't love "iota" but I can accept it too. 
 Other names of Phobos2 can be improved.


I can be happy with either 'retro' or 'reverse'. My feeling on 'iota' used 
to be "It's not great, but I'm fine with it". But now I can't remember what 
the hell it does; no idea. The only things that come to mind are "Dyslexic 
Integer to ASCII conversion", and Futurama's "Tiny Iota? I could never be as 
good as him. He was a great Blurnsball player."

Feb 14 2010

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

Nick Sabalausky wrote:
 "bearophile" <bearophileHUGS lycos.com> wrote in message 
 news:hl9ipc$26r1$1 digitalmars.com...
 Andrei Alexandrescu:
 I don't mind "reversed" but it's longer than "retro" and the convention
 doesn't scale. For example, both active and passive forms of "split"
 look the same.


 Other names of Phobos2 can be improved.


 I can be happy with either 'retro' or 'reverse'. My feeling on 'iota' used 
 to be "It's not great, but I'm fine with it". But now I can't remember what 
 the hell it does; no idea. The only things that come to mind are "Dyslexic 
 Integer to ASCII conversion", and Futurama's "Tiny Iota? I could never be as 
 good as him. He was a great Blurnsball player."


retro does have something going for it that iota doesn't. Everybody I 
talked to who saw "retro" in my article on ranges knew immediately what 
it does, and furthermore remembered the name later.

Andrei

Feb 14 2010

KennyTM~ <kennytm gmail.com> writes:

On Feb 15, 10 02:08, Andrei Alexandrescu wrote:
 bearophile wrote:
 Mike James:
 1. Contrawise
 2. Rearward
 3. AssBackwards
 4. Reorientated
 5. Turnedabout
 6. Turnedaround
 7. Inversified
 8. Flipped
 9. Refluxed
 10. VolteFace

 or how about Reverse...


 Wonderful, I elect you the official namer for Phobos :-)
 And I think Andrei meant a list of all the bad names in Phobos :-)
 What about "reversed"? :-)


 I don't mind "reversed" but it's longer than "retro" and the convention
 doesn't scale. For example, both active and passive forms of "split"
 look the same.

 Andrei


Why do you want to perform an in-place split?

Feb 16 2010

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

Mike James wrote:
 Andrei Alexandrescu Wrote:
 
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.

 Andrei


 1.   Contrawise
 2.   Rearward
 3.   AssBackwards
 4.   Reorientated
 5.   Turnedabout
 6.   Turnedaround
 7.   Inversified
 8.   Flipped
 9.   Refluxed
 10. VolteFace
 
 or how about Reverse...
 
 -=mike=-


I meant a list with other cases (aside from this particular one) in 
which choices of names were unfortunate.

I thought the following is clear but let me state it: in this particular 
case, using "reverse" is not desirable because the name already exists 
as an array property. If we drop the existing feature and choose 
"reverse" for the new feature, code will silently change semantics.


Andrei

Feb 14 2010

Mike James <foo bar.com> writes:

Andrei Alexandrescu Wrote:

 Mike James wrote:
 Andrei Alexandrescu Wrote:
 
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.

 Andrei


 1.   Contrawise
 2.   Rearward
 3.   AssBackwards
 4.   Reorientated
 5.   Turnedabout
 6.   Turnedaround
 7.   Inversified
 8.   Flipped
 9.   Refluxed
 10. VolteFace
 
 or how about Reverse...
 
 -=mike=-


 I meant a list with other cases (aside from this particular one) in 
 which choices of names were unfortunate.
 
 I thought the following is clear but let me state it: in this particular 
 case, using "reverse" is not desirable because the name already exists 
 as an array property. If we drop the existing feature and choose 
 "reverse" for the new feature, code will silently change semantics.
 
 
 Andrei


I can understand that, but the problem is - the dictionary definition of
'retro' is 'associated with or revived from the past'. It doesn't correctly
describe the action. It could generate many hours of semiotic arguements... ;=)

-=mike=-

Feb 14 2010

"Nick Sabalausky" <a a.a> writes:

"Mike James" <foo bar.com> wrote in message 
news:hl9i1q$24m0$1 digitalmars.com...
 I can understand that, but the problem is - the dictionary definition of 
 'retro' is 'associated with or revived from the past'. It doesn't 
 correctly describe the action. It could generate many hours of semiotic 
 arguements... ;=)


I think there's probably a lot of cases where dictionary definitions don't 
quite match a word's usage in the programming world. "Kill", "thread", 
"string", "rake" (the ruby build tool) all come to mind. Of course, "retro" 
might be argued to be more of a stretch than some of those, but you can also 
think of "retro" just referring to the prefix "retro" (which does basically 
just mean "backwards", AIUI) rather than the actual word "retro".

Feb 14 2010

Mike James <foo bar.com> writes:

Andrei Alexandrescu Wrote:

 Mike James wrote:
 Andrei Alexandrescu Wrote:
 
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.

 Andrei


 1.   Contrawise
 2.   Rearward
 3.   AssBackwards
 4.   Reorientated
 5.   Turnedabout
 6.   Turnedaround
 7.   Inversified
 8.   Flipped
 9.   Refluxed
 10. VolteFace
 
 or how about Reverse...
 
 -=mike=-


 I meant a list with other cases (aside from this particular one) in 
 which choices of names were unfortunate.
 
 I thought the following is clear but let me state it: in this particular 
 case, using "reverse" is not desirable because the name already exists 
 as an array property. If we drop the existing feature and choose 
 "reverse" for the new feature, code will silently change semantics.
 
 
 Andrei


Interestingly enough, although 'invert' means turning something upside down,
according to the dictionary, it can also imply reversing something...

would 'Invert' be applicable?

-=mike=-

Feb 14 2010

Justin Johansson <no spam.com> writes:

Andrei Alexandrescu wrote:
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name 
 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.
 
 Andrei


How about

esrever

with credit for original idea going to highly creative Unix
script language designers as in

if
   ...
fi

esrever has attributes (b) and (c) (definitely memorable).
(a), well no, arguably it's not short.  so I guess it really
is a no brainer, then.  How about

ver

)-: nitsuJ

Feb 14 2010

Ary Borenszweig <ary esperanto.org.ar> writes:

Justin Johansson wrote:
 Andrei Alexandrescu wrote:
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name 
 that was (a) short, (b) different from "reverse", (c) memorable. It is 
 understood that other paint colors are available, but please don't 
 forget to give a little love to the painter. :o) It would be of course 
 best if names that arguably hurt the language were changed, so please 
 compile a list.

 Andrei


 How about
 
 esrever


Nah, hcaerof

Feb 14 2010

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

retard wrote:
 Sun, 14 Feb 2010 11:18:02 -0600, Andrei Alexandrescu wrote:
 
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think "reverse"
 is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or design
 from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning isn't
 very clear. "reverse" would be a better name.


 (the names are very clever and funny, but that shouldn't be the point
 of a name, a name should be clear).


 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.


 It sounds like a flaw in the language design if the symbols for reversing 
 arrays and ranges somehow conflict.


There are two operations: reverse the thing in place, and span it in 
retrograde order.

Andrei

Feb 14 2010

Ary Borenszweig <ary esperanto.org.ar> writes:

Andrei Alexandrescu wrote:
 retard wrote:
 Sun, 14 Feb 2010 11:18:02 -0600, Andrei Alexandrescu wrote:

 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think "reverse"
 is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or design
 from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning isn't
 very clear. "reverse" would be a better name.


 (the names are very clever and funny, but that shouldn't be the point
 of a name, a name should be clear).


 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.


 It sounds like a flaw in the language design if the symbols for 
 reversing arrays and ranges somehow conflict.


 There are two operations: reverse the thing in place, and span it in 
 retrograde order.
 
 Andrei


asterite deep-water:~$ irb
irb(main):001:0> a = [1, 2, 3]
=> [1, 2, 3]
irb(main):002:0> a.reverse
=> [3, 2, 1]
irb(main):003:0> a
=> [1, 2, 3]
irb(main):004:0> a.reverse!
=> [3, 2, 1]
irb(main):005:0> a
=> [3, 2, 1]
irb(main):006:0>

Aaaah... ruby <3

Feb 15 2010

Michel Fortin <michel.fortin michelf.com> writes:

On 2010-02-15 09:04:11 -0500, Leandro Lucarella <llucax gmail.com> said:

 Andrei Alexandrescu, el 14 de febrero a las 20:24 me escribiste:
 There are two operations: reverse the thing in place, and span it in
 retrograde order.


 I think reverse (in-place) and reversed (returns a range that iterates in
 reverse order) are *very* clear in terms of that distinction.


But now how do you distinguish between a function returning the 
reversed form of something and a function returning true when that 
thing is reversed?

:-)

In Ruby syntax things are generally pretty easy:

	something.reverse!  # reverse in place ('dangerous!' method)
	something.reverse   # reverse a copy
	something.reversed? # return whether something is reversed or not

Cocoa would use a slightly different notation:

	[something reverse];           // reverse in place
	[something reversedSomething]; // reverse a copy
	[something isReversed];        // return whether something is reversed or not

Both conventions are very clear and scale well even for words like 
'split' which are identical in their past and present tense.

It's unclear to me how we want this to be done in D...

	something.reverse();  // reverse in place
	something.reversed;   // reverse a copy
	something.reversed(); //   ditto
	something.reverse();  //   ditto
	something.reversed;   // return whether something is reversed or not
	something.isReversed; //   ditto

If we want some consistency, someone with authority over Phobos will 
have to draw some guidelines about this, and sooner the better.

-- 
Michel Fortin
michel.fortin michelf.com
http://michelf.com/

Feb 15 2010

Jacob Carlborg <doob me.com> writes:

On 2/14/10 18:18, Andrei Alexandrescu wrote:
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.

 Andrei


I never understood the reason for that the names need to be short. I 
think the most important thing is that the names are clear. Just look at 
the C standard library, it's horrible, almost every name is an 
abbreviation of some kind.

Feb 15 2010

Jonathan M Davis <jmdavisProg gmail.com> writes:

Jacob Carlborg wrote:
 
 I never understood the reason for that the names need to be short. I
 think the most important thing is that the names are clear. Just look at
 the C standard library, it's horrible, almost every name is an
 abbreviation of some kind.


Clarity is very important, but if you have long names which are used 
frequently, it can quickly result in long lines of code which end up on 
multiple lines and can be hard to read. If a word isn't used very often, 
then it's not that big a deal, but the more often it's used - especially 
when it can be used multiple times on the same line - the worse it gets. 
Really, the ideal situation is to find words which are short and clear, but 
a balance must be struck between the two regardless. Too long and it's 
cumbersome. Too short and it's likely to be unclear.

There's no question that programmers often use words for variable names and 
such which are ludicrously short and unclear, but long words can be a 
problem too.

- Jonathan M Davis

Feb 15 2010

Michel Fortin <michel.fortin michelf.com> writes:

On 2010-02-15 08:59:43 -0500, Jonathan M Davis <jmdavisProg gmail.com> said:

 Clarity is very important, but if you have long names which are used
 frequently, it can quickly result in long lines of code which end up on
 multiple lines and can be hard to read. If a word isn't used very often,
 then it's not that big a deal, but the more often it's used - especially
 when it can be used multiple times on the same line - the worse it gets.


Well, the problem is that whether you're using something often or not 
depends on the context. If in a context your function name is used once 
or two, but in another it's used a lot, which prevails: shortness or 
clarity?

I'd tend to put clarity over short names in D because the language 
makes it very easy to create shorter aliases limited in scope when the 
need arise. But you shouldn't repeat the argument types nor the 
module's name: the language takes care of that for you.


 Really, the ideal situation is to find words which are short and clear, but
 a balance must be struck between the two regardless. Too long and it's
 cumbersome. Too short and it's likely to be unclear.


 There's no question that programmers often use words for variable names and
 such which are ludicrously short and unclear, but long words can be a
 problem too.


I think it's a question of locality. The broader is the scope of a name 
the more self-explaining the name should be. As an extreme example, I 
don't mind much seeing a local variable named 'x' in a short function, 
but I wouldn't accept that as a member variable in a class, and even 
less for a global variable.

It's easy for someone to create short names when he is all absorbed in 
what he's doing. But I think it generally takes some detachment to get 
the names right for a public API. Ideally, API names should be 
understandable as soon as you understand the underlying concepts. But 
even more important is that __functions should never be understood 
wrong__, the name should be clear enough to ensure that.

I don't think std.range fare very well at this readability test. Take 
this example:

	int[] array = [1,2,3,4,5,6,7,8,9];
	auto five = take(5, array);
	writeln(array); // what are you expecting here?

In the case above, 'take' returns a range that lazily takes N elements 
when you iterate over it. If you don't use the returned range, 'take' 
is as good as a no-op. But this subtle interaction isn't very clear 
when you just read the code.

Last week I defined my own function named 'take' for some kind of 
parser, advancing the range by the number of specified elements and 
returning an array of all the 'taken' elements. Then I realized it had 
the same name as the one above but with this subtle difference in 
semantics, subtle but very important for what I was doing. I renamed my 
function since then to make things less confusing, but I'm still a 
little shaken by this whole incident.

I think the lazy nature of 'take' should be visible when calling the 
function. This could be achieved by a name change, or perhaps in 
another way.

-- 
Michel Fortin
michel.fortin michelf.com
http://michelf.com/

Feb 15 2010

dsimcha <dsimcha yahoo.com> writes:

== Quote from Jacob Carlborg (doob me.com)'s article
 I never understood the reason for that the names need to be short. I
 think the most important thing is that the names are clear. Just look at
 the C standard library, it's horrible, almost every name is an
 abbreviation of some kind.


Names should be short to save typing and clutter.  Of course, clarity also
matters.  I tend to prefer short names for frequently used language and library
constructs that everyone who has been using the language for more than two weeks
should know.  Longer names have their use in **your** programs and in less
frequently used constructs, where the overhead of memorizing what a short,
unclear
name means is less than the overhead of typing a long name.

Feb 15 2010

bearophile <bearophileHUGS lycos.com> writes:

dsimcha:
 I tend to prefer short names for frequently used language and library
 constructs that everyone who has been using the language for more than two
weeks
 should know.  Longer names have their use in **your** programs and in less
 frequently used constructs, where the overhead of memorizing what a short,
unclear
 name means is less than the overhead of typing a long name.


http://en.wikipedia.org/wiki/Zipf_law

Bye,
bearophile

Feb 15 2010

Justin Johansson <no spam.com> writes:

 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.

 Andrei


 I never understood the reason for that the names need to be short. I 
 think the most important thing is that the names are clear. Just look at 
 the C standard library, it's horrible, almost every name is an 
 abbreviation of some kind.


Are you trying to start a flame war?
What's wrong with LISP's car and cdr?

Isn't it obvious to all and sundry that car is the head element
of a singly linked list and cdr is the rest of the list with the
head element removed?

Justin Johansson :-) :-) :-)

Feb 15 2010

=?ISO-8859-1?Q?Pelle_M=E5nsson?= <pelle.mansson gmail.com> writes:

On 02/15/2010 09:44 PM, Justin Johansson wrote:
 Isn't it obvious to all and sundry that car is the head element
 of a singly linked list and cdr is the rest of the list with the
 head element removed?


Actually, car is the reference to the first item in the cons cell, and 
cdr is the second. Not just lists, you know. :)

Feb 15 2010

Yigal Chripun <yigal100 gmail.com> writes:

On 15/02/2010 15:00, Jacob Carlborg wrote:
 On 2/14/10 18:18, Andrei Alexandrescu wrote:
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.

 Andrei


 I never understood the reason for that the names need to be short. I
 think the most important thing is that the names are clear. Just look at
 the C standard library, it's horrible, almost every name is an
 abbreviation of some kind.


C was designed in the dark ages when programmers actually tried to save 
bytes in their extremely limited hardware. That same age brought us the 
tab character, Y2k bug and FORTRAN.

Feb 16 2010

Yigal Chripun <yigal100 gmail.com> writes:

On 14/02/2010 19:18, Andrei Alexandrescu wrote:
 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think
 "reverse" is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point of
 a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.

 Andrei


As I said multitude of times before, if you want D to be commercially 
successful, you need to change your priorities.
the *most* important thing to have is _clear_ and _understandable_ names 
by a wide international audience. The *least* important thing is shortness.

you might argue as long as you want that C++/D is technically superior 
to Java, but fact remains that Java is the favorite language in 
enterprise. One huge factor which helps this is of course the clear 
naming scheme in its stdlib.

Feb 16 2010

torhu <no spam.invalid> writes:

On 14.02.2010 11:12, Jacob Carlborg wrote:
 On 2/14/10 09:14, Jonathan M Davis wrote:
  Though I must say that I find retro to be a bit funny. I would have expected
  it to be reverse. It would be clearer, I think, but it's not like it's hard
  to find out what retro does and remember it.

  - Jonathan M Davis


 It iterates backwards, all the way back to the 50s. I think "reverse" is
 a much better word.



foreach (thing; backwards(lotsOfThings))
{

}


'backwards' would be fine by me.  But then I don't seem to iterate in 
reverse a whole lot, so it doesn't bother me that it's twice a long as 
'retro'.  Is that really a problem?

Feb 15 2010

"Adam D. Ruppe" <destructionator gmail.com> writes:

On Sun, Feb 14, 2010 at 02:26:36PM -0500, bearophile wrote:
 For me "retro" is acceptable.


I like it too. Retro style never even came to my mind; I thought of
retro rockets - the rockets that fire in reverse.

-- 
Adam D. Ruppe
http://arsdnet.net

Feb 14 2010

Igor Lesik <curoles yahoo.com> writes:

opposite

not very long name, bears the meaning

Feb 14 2010

"Nick Sabalausky" <a a.a> writes:

"Igor Lesik" <curoles yahoo.com> wrote in message 
news:mailman.58.1266181553.4461.digitalmars-d puremagic.com...
 opposite

 not very long name, bears the meaning


"opposite" (and "inverse" as someone suggested) can have a lot of different 
meanings. Too ambiguous, IMO.

Feb 14 2010

retard <re tard.com.invalid> writes:

Sun, 14 Feb 2010 11:18:02 -0600, Andrei Alexandrescu wrote:

 Leandro Lucarella wrote:
 Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

 It iterates backwards, all the way back to the 50s. I think "reverse"
 is a much better word.



 My dictionary says: "retro": imitative of a style, fashion, or design
 from the recent past.

 It's an amusing name in the way Andrei likes it, but the meaning isn't
 very clear. "reverse" would be a better name.


 This is a pattern in Andrei, which I think it really hurts the language
 (the names are very clever and funny, but that shouldn't be the point
 of a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It is
 understood that other paint colors are available, but please don't
 forget to give a little love to the painter. :o) It would be of course
 best if names that arguably hurt the language were changed, so please
 compile a list.


It sounds like a flaw in the language design if the symbols for reversing 
arrays and ranges somehow conflict.

Feb 14 2010

retard <re tard.com.invalid> writes:

Sun, 14 Feb 2010 14:26:36 -0500, bearophile wrote:

 Andrei Alexandrescu:
 I don't mind "reversed" but it's longer than "retro" and the convention
 doesn't scale. For example, both active and passive forms of "split"
 look the same.


 For me "retro" is acceptable. I don't love "iota" but I can accept it
 too. Other names of Phobos2 can be improved.


Agreed, these names are really confusing. To me itoa sounds like "integer 
to string" and iota "string to integer" ("to".reverse == "ot").

I can imagine using retro in code such as:

import pacman.PacmanGame;

void main() {
  if (userWants3DVoodoo) {
    // real time 3d rendering with photon mapping and 9.1 192/24 sounds
    (new PacmanGame).start();
  } else {
    // nice 8-bit graphics with mono 4-bit sound
    retro(new PacmanGame).start();
  }
}

Feb 14 2010

Daniel Murphy <yebbliesnospam gmail.com> writes:

Andrei Alexandrescu Wrote:

 Gone, that is. Walter agreed to remove it.
 
 To achieve the functionality of
 
 foreach_reverse (r) { ... }
 
 use
 
 foreach (retro(r)) { ... }
 
 using retro in std.range.
 
 
 Andrei


What about where foreach is being done over something other than a range?
eg.
foreach(i; 1..100)
foreach(v; structwithopapply)

Feb 14 2010

bearophile <bearophileHUGS lycos.com> writes:

Daniel Murphy:
 What about where foreach is being done over something other than a range?
 eg.
 foreach(i; 1..100)
 foreach(v; structwithopapply)


The first can be done turning an interval into syntax sugar for iota(1,100):
The foreach(i; retro(1 .. 100))
Otherwise the interval syntax can grow the step, as in Python and other
languages (in D the step might even be a compile-time constant):
The foreach(i; 1 .. 100 : -1)

The second gives no problems if retro is well done:
foreach(v; retro(structWithopApplyReverse))

Bye,
bearophile

Feb 14 2010

bearophile <bearophileHUGS lycos.com> writes:

 The foreach(i; 1 .. 100 : -1)


Sorry, I meant:
foreach(i; 99 .. 0 : -1)

Bye,
bearophile

Feb 14 2010

Michel Fortin <michel.fortin michelf.com> writes:

On 2010-02-14 07:15:55 -0500, bearophile <bearophileHUGS lycos.com> said:

 The first can be done turning an interval into syntax sugar for iota(1,100):
 The foreach(i; retro(1 .. 100))


I'm all for it, but we'll need to have 1..100 mapped to a new interval 
type for this to work. Then you can easily implement this (among many 
other interesting things):

	auto reverse(Interval!int interval) { ... }


-- 
Michel Fortin
michel.fortin michelf.com
http://michelf.com/

Feb 14 2010

dsimcha <dsimcha yahoo.com> writes:

== Quote from bearophile (bearophileHUGS lycos.com)'s article
 The second gives no problems if retro is well done:
 foreach(v; retro(structWithopApplyReverse))
 Bye,
 bearophile


I have no idea how you would implement retro such that it worked with
opApplyReverse.

Feb 14 2010

dsimcha <dsimcha yahoo.com> writes:

== Quote from Daniel Murphy (yebbliesnospam gmail.com)'s article
 Andrei Alexandrescu Wrote:
 Gone, that is. Walter agreed to remove it.

 To achieve the functionality of

 foreach_reverse (r) { ... }

 use

 foreach (retro(r)) { ... }

 using retro in std.range.


 Andrei


 eg.
 foreach(i; 1..100)
 foreach(v; structwithopapply)


In general, now that we've decided to keep opApply, std.range needs to be
reworked
a little to make it coexist as peacefully as possible with ranges.  For this
case,
I guess retro could simply have an opApply method that forwards to
structwithopapply's opApplyReverse method.

Feb 14 2010

"Lars T. Kyllingstad" <public kyllingen.NOSPAMnet> writes:

Andrei Alexandrescu wrote:
 Gone, that is. Walter agreed to remove it.
 
 To achieve the functionality of
 
 foreach_reverse (r) { ... }
 
 use
 
 foreach (retro(r)) { ... }
 
 using retro in std.range.



Let me first say that I think it's great that one of D's ugliest 
keywords is going away. But does retro (or ranges in general) support 
iteration over both index and element?

   foreach_reverse(i, e; foo) { ... }

-Lars

Feb 14 2010

grauzone <none example.net> writes:

Lars T. Kyllingstad wrote:
 Andrei Alexandrescu wrote:
 Gone, that is. Walter agreed to remove it.

 To achieve the functionality of

 foreach_reverse (r) { ... }

 use

 foreach (retro(r)) { ... }

 using retro in std.range.




Now all what's left to do is to make it as efficient as the builtin 
functionality.

 
 Let me first say that I think it's great that one of D's ugliest 
 keywords is going away. But does retro (or ranges in general) support 
 iteration over both index and element?
 
   foreach_reverse(i, e; foo) { ... }


And will it be able to parse utf-8 backwards?

I assume proper utf-8 support with ranges (or whatever is planned) isn't 
implemented yet, so I didn't test it.

 -Lars

Feb 14 2010

dsimcha <dsimcha yahoo.com> writes:

== Quote from Lars T. Kyllingstad (public kyllingen.NOSPAMnet)'s article
 Andrei Alexandrescu wrote:
 Gone, that is. Walter agreed to remove it.

 To achieve the functionality of

 foreach_reverse (r) { ... }

 use

 foreach (retro(r)) { ... }

 using retro in std.range.


 keywords is going away. But does retro (or ranges in general) support
 iteration over both index and element?
    foreach_reverse(i, e; foo) { ... }
 -Lars


Bug 3519:  http://d.puremagic.com/issues/show_bug.cgi?id=3519

Feb 14 2010

Mike James <foo bar.com> writes:

Andrei Alexandrescu Wrote:

 Gone, that is. Walter agreed to remove it.
 
 To achieve the functionality of
 
 foreach_reverse (r) { ... }
 
 use
 
 foreach (retro(r)) { ... }
 
 using retro in std.range.
 
 
 Andrei


I think Reverse would have been a better title. Retro sounds like you might be
using only 8088 assembler instructions in the output...

-=mike=-

Feb 14 2010

Bane <branimir.milosavljevic gmail.com> writes:

Mike James Wrote:

 Andrei Alexandrescu Wrote:
 
 Gone, that is. Walter agreed to remove it.
 
 To achieve the functionality of
 
 foreach_reverse (r) { ... }
 
 use
 
 foreach (retro(r)) { ... }
 
 using retro in std.range.
 
 
 Andrei


 I think Reverse would have been a better title. Retro sounds like you might be
using only 8088 assembler instructions in the output...
 
 -=mike=-


Read about a guy that used preprocessor to change C keywords to his taste on
company project. Nearly caused heart attack to next guy in line to maintain
that code. Maybe we could keep both keywords :D

Feb 14 2010

Leandro Lucarella <llucax gmail.com> writes:

Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
 On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:
 
It iterates backwards, all the way back to the 50s. I think
"reverse" is a much better word.


 Agree.
 
 My dictionary says: "retro": imitative of a style, fashion, or
 design from the recent past.
 
 It's an amusing name in the way Andrei likes it, but the meaning
 isn't very clear. "reverse" would be a better name.


This is a pattern in Andrei, which I think it really hurts the language
(the names are very clever and funny, but that shouldn't be the point of
a name, a name should be clear).

-- 
Leandro Lucarella (AKA luca)                     http://llucax.com.ar/
----------------------------------------------------------------------
GPG Key: 5F5A8D05 (F8CD F9A7 BF00 5431 4145  104C 949E BFB6 5F5A 8D05)
----------------------------------------------------------------------

Feb 14 2010

Leandro Lucarella <llucax gmail.com> writes:

Andrei Alexandrescu, el 14 de febrero a las 11:18 me escribiste:
 Leandro Lucarella wrote:
Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

It iterates backwards, all the way back to the 50s. I think
"reverse" is a much better word.



My dictionary says: "retro": imitative of a style, fashion, or
design from the recent past.

It's an amusing name in the way Andrei likes it, but the meaning
isn't very clear. "reverse" would be a better name.


This is a pattern in Andrei, which I think it really hurts the language
(the names are very clever and funny, but that shouldn't be the point of
a name, a name should be clear).


 At least in this case being funny was not the point. I needed a name
 that was (a) short, (b) different from "reverse", (c) memorable. It
 is understood that other paint colors are available, but please
 don't forget to give a little love to the painter. :o) It would be


I'm not trying to hurt you :)

I just pointing out that you sometimes pick up clever or creative or
niche names, which might look like a good idea to you but it's not for me.
They are different points of view, I'm sure a lot of people would "look,
D has these very clever names, it sure is a good language", but I think,
from a practical point of view, that it's a bad idea because they are less
natural and harder to learn, remember and *read*.

 of course best if names that arguably hurt the language were
 changed, so please compile a list.


Well, they were discussed several times, sometimes with huge threads (like
the range methods names). iota() is another really hard to
remember/understand name for me (I said that before). I just didn't know
what iota() was before you used it in phobos. I even couldn't follow some
examples before I searched what iota was (which it took me some time
because I was a little embarrassed that I didn't knew its meaning =).

-- 
Leandro Lucarella (AKA luca)                     http://llucax.com.ar/
----------------------------------------------------------------------
GPG Key: 5F5A8D05 (F8CD F9A7 BF00 5431 4145  104C 949E BFB6 5F5A 8D05)
----------------------------------------------------------------------

Feb 15 2010

Leandro Lucarella <llucax gmail.com> writes:

Andrei Alexandrescu, el 14 de febrero a las 12:08 me escribiste:
 bearophile wrote:
Mike James:
1.   Contrawise
2.   Rearward
3.   AssBackwards
4.   Reorientated
5.   Turnedabout
6.   Turnedaround
7.   Inversified
8.   Flipped
9.   Refluxed
10. VolteFace

or how about Reverse...


Wonderful, I elect you the official namer for Phobos :-)
And I think Andrei meant a list of all the bad names in Phobos :-)
What about "reversed"? :-)


 I don't mind "reversed" but it's longer than "retro" and the
 convention doesn't scale. For example, both active and passive forms
 of "split" look the same.


Well, english sucks, you can't fix that ;)

-- 
Leandro Lucarella (AKA luca)                     http://llucax.com.ar/
----------------------------------------------------------------------
GPG Key: 5F5A8D05 (F8CD F9A7 BF00 5431 4145  104C 949E BFB6 5F5A 8D05)
----------------------------------------------------------------------

Feb 15 2010

Leandro Lucarella <llucax gmail.com> writes:

Andrei Alexandrescu, el 14 de febrero a las 20:24 me escribiste:
 retard wrote:
Sun, 14 Feb 2010 11:18:02 -0600, Andrei Alexandrescu wrote:

Leandro Lucarella wrote:
Michel Fortin, el 14 de febrero a las 07:48 me escribiste:
On 2010-02-14 05:12:41 -0500, Jacob Carlborg <doob me.com> said:

It iterates backwards, all the way back to the 50s. I think "reverse"
is a much better word.



My dictionary says: "retro": imitative of a style, fashion, or design
from the recent past.

It's an amusing name in the way Andrei likes it, but the meaning isn't
very clear. "reverse" would be a better name.


(the names are very clever and funny, but that shouldn't be the point
of a name, a name should be clear).


that was (a) short, (b) different from "reverse", (c) memorable. It is
understood that other paint colors are available, but please don't
forget to give a little love to the painter. :o) It would be of course
best if names that arguably hurt the language were changed, so please
compile a list.


It sounds like a flaw in the language design if the symbols for
reversing arrays and ranges somehow conflict.


 There are two operations: reverse the thing in place, and span it in
 retrograde order.


I think reverse (in-place) and reversed (returns a range that iterates in
reverse order) are *very* clear in terms of that distinction.

-- 
Leandro Lucarella (AKA luca)                     http://llucax.com.ar/
----------------------------------------------------------------------
GPG Key: 5F5A8D05 (F8CD F9A7 BF00 5431 4145  104C 949E BFB6 5F5A 8D05)
----------------------------------------------------------------------

Feb 15 2010

"Steven Schveighoffer" <schveiguy yahoo.com> writes:

On Sun, 14 Feb 2010 00:53:31 -0500, Andrei Alexandrescu  
<SeeWebsiteForEmail erdani.org> wrote:

 Gone, that is. Walter agreed to remove it.

 To achieve the functionality of

 foreach_reverse (r) { ... }

 use

 foreach (retro(r)) { ... }

 using retro in std.range.


Will retro work on AA's?

Other than that (and how to do foreach(1..100) that others have brought  
up) I think this is a great move.

BTW, for those bemoaning the loss of opApplyReverse, it is easy to change  
this:

struct S(T)
{
    int opApplyReverse(int delegate(ref T t) dg) {...}
}

S!int s;
foreach_reverse(i; s) {...}

into this:

struct S(T)
{
    int inReverse(int delegate(ref T t) dg) {...}
}

S!int s;
foreach(i; &s.inReverse){...}

Of course, I'd prefer it without the &, but that is a separate issue (see  
bug http://d.puremagic.com/issues/show_bug.cgi?id=2498)

Also, while your attention is focused on foreach, look at this bug:  
http://d.puremagic.com/issues/show_bug.cgi?id=2443

:)

-Steve

Feb 15 2010

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