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digitalmars.D.learn - D2 map trouble

reply "Nick Sabalausky" <a a.a> writes:
Trying to convert some D1 code to D2:

On 2.047, I'm trying to do this:

import std.string;
void foo(string str)
{
str =
  std.algorithm.map!(
   (char a) { return inPattern(a, [digits, letters])? a : '_'; }
  )(str);
}

And I'm getting:

delegate std.algorithm.__dgliteral1 cannot access frame of function 
__dgliteral1

What's going on? How do I do it right? I figure I probably have some sort of 
problem with strings being immutable(char)[] instead of char[], but it 
doesn't look like that's the issue it's complaining about. Also, in this 
particular case, I'm not concerned about multi-unit UTF-8 characters.
Jul 27 2010
next sibling parent reply "Nick Sabalausky" <a a.a> writes:
"Nick Sabalausky" <a a.a> wrote in message 
news:i2no7g$euv$1 digitalmars.com...

 Trying to convert some D1 code to D2:

 On 2.047, I'm trying to do this:

 import std.string;
 void foo(string str)
 {
 str =
  std.algorithm.map!(
   (char a) { return inPattern(a, [digits, letters])? a : '_'; }
  )(str);
 }

 And I'm getting:

 delegate std.algorithm.__dgliteral1 cannot access frame of function 
 __dgliteral1

 What's going on? How do I do it right? I figure I probably have some sort 
 of problem with strings being immutable(char)[] instead of char[], but it 
 doesn't look like that's the issue it's complaining about. Also, in this 
 particular case, I'm not concerned about multi-unit UTF-8 characters.


In my particular case, I've just switched to regex:

import std.regex;
str = replace(str, regex("[^a-zA-Z0-9]"), "_");

But I am still curious to hear what exactly was going on with map.
Jul 27 2010
next sibling parent Dmitry Olshansky <dmitry.olsh gmail.com> writes:
On 28.07.2010 3:06, Nick Sabalausky wrote:

 "Nick Sabalausky"<a a.a>  wrote in message
 news:i2no7g$euv$1 digitalmars.com...
    

 Trying to convert some D1 code to D2:

 On 2.047, I'm trying to do this:

 import std.string;
 void foo(string str)
 {
 str =
   std.algorithm.map!(
    (char a) { return inPattern(a, [digits, letters])? a : '_'; }
   )(str);
 }

 And I'm getting:

 delegate std.algorithm.__dgliteral1 cannot access frame of function
 __dgliteral1

 What's going on? How do I do it right? I figure I probably have some sort
 of problem with strings being immutable(char)[] instead of char[], but it
 doesn't look like that's the issue it's complaining about. Also, in this
 particular case, I'm not concerned about multi-unit UTF-8 characters.


      


 In my particular case, I've just switched to regex:

 import std.regex;
 str = replace(str, regex("[^a-zA-Z0-9]"), "_");

 But I am still curious to hear what exactly was going on with map.


    


AFAIK weird compiler bug. See also thread about std.find which involves 
the problem with map 
http://www.digitalmars.com/d/archives/digitalmars/D/Improving_std.algorithm.find_113545.html#N113558


-- 
Dmitry Olshansky
Jul 27 2010
prev sibling parent reply Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Wed, Jul 28, 2010 at 01:06, Nick Sabalausky <a a.a> wrote:


 "Nick Sabalausky" <a a.a> wrote in message
 news:i2no7g$euv$1 digitalmars.com...

 Trying to convert some D1 code to D2:

 On 2.047, I'm trying to do this:

 import std.string;
 void foo(string str)
 {
 str =
  std.algorithm.map!(
   (char a) { return inPattern(a, [digits, letters])? a : '_'; }
  )(str);
 }

 And I'm getting:

 delegate std.algorithm.__dgliteral1 cannot access frame of function
 __dgliteral1

 What's going on? How do I do it right? I figure I probably have some sort
 of problem with strings being immutable(char)[] instead of char[], but it
 doesn't look like that's the issue it's complaining about. Also, in this
 particular case, I'm not concerned about multi-unit UTF-8 characters.


 In my particular case, I've just switched to regex:

 import std.regex;
 str = replace(str, regex("[^a-zA-Z0-9]"), "_");

 But I am still curious to hear what exactly was going on with map.


It's an error I get on a weekly basis :-(
Either returning a map with an anonymous function or using it as you do. I
gather the Map template in std.algo is unable to have access to your closure
literal, as it is inside foo.

A possible workaround is having the anonymous function as a standard, named,
free function and use this inside foo. But in that case, why have anonymous
functions in D?
Another is to use 'string functions', I think. I can test right now, but
something like might work:

void foo(string str)
{
 str =
 std.algorithm.map!q{
  inPattern(a, [digits, letters])? a : '_';
}
  (str);
}

But then I guess inPattern must be visible from std.algorithm.

So my current conclusion it that it's more a limitation of anonymous
closures than a limitation in map.

Philippe
Jul 28 2010
parent "Nick Sabalausky" <a a.a> writes:
"Philippe Sigaud" <philippe.sigaud gmail.com> wrote in message 
news:mailman.32.1280323222.13841.digitalmars-d-learn puremagic.com...

 void foo(string str)
 {
 str =
 std.algorithm.map!q{
  inPattern(a, [digits, letters])? a : '_';
 }
  (str);
 }

 But then I guess inPattern must be visible from std.algorithm.

 So my current conclusion it that it's more a limitation of anonymous
 closures than a limitation in map.


*sigh*, If D allowed something like this:

mixin string map() { return "code here"; }
map();

As an alternative to or intead of this:

string map() { return "code here"; }
mixin(map());

As I've suggested before (it only got accepted for template mixins, not 
string mixins), then map's string-style predicates could be made to be 
evaluated in the proper context without screwing up map's standard interface 
by requiring it to be called with "mixin(...)".
Jul 28 2010
prev sibling parent reply Pelle <pelle.mansson gmail.com> writes:
On 07/28/2010 12:57 AM, Nick Sabalausky wrote:

 Trying to convert some D1 code to D2:

 On 2.047, I'm trying to do this:

 import std.string;
 void foo(string str)
 {
 str =
    std.algorithm.map!(
     (char a) { return inPattern(a, [digits, letters])? a : '_'; }
    )(str);
 }

 And I'm getting:

 delegate std.algorithm.__dgliteral1 cannot access frame of function
 __dgliteral1

 What's going on? How do I do it right? I figure I probably have some sort of
 problem with strings being immutable(char)[] instead of char[], but it
 doesn't look like that's the issue it's complaining about. Also, in this
 particular case, I'm not concerned about multi-unit UTF-8 characters.


This is a compiler bug. Easy workaround:

auto fn = (char a) { ... };
str = map!fn(str);
Jul 28 2010
parent reply Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Wed, Jul 28, 2010 at 16:51, Pelle <pelle.mansson gmail.com> wrote:


 This is a compiler bug. Easy workaround:

 auto fn = (char a) { ... };
 str = map!fn(str);


Is it on bugzilla?

Philippe
Jul 28 2010
parent bearophile <bearophileHUGS lycos.com> writes:
Philippe Sigaud:

 Is it on bugzilla?


If not present you can add it here:
http://d.puremagic.com/issues/show_bug.cgi?id=4264

Bye,
bearophile
Jul 28 2010