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digitalmars.D.bugs - [Issue 8560] New: Strange behavior of lambda expressions

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=8560

           Summary: Strange behavior of lambda expressions
           Product: D
           Version: D2
          Platform: x86_64
        OS/Version: Linux
            Status: NEW
          Severity: major
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: iu.biryukov gmail.com


--- Comment #0 from ilya <iu.biryukov gmail.com> 2012-08-18 13:45:45 PDT ---
I came up with this code while playing around with D:

import std.stdio;

public class Test(alias fun, alias fun2) {
  void doIt() {
    fun();
    fun2();
  }
}


void main() {
  (new Test!(
      () => {writeln("fun1");},
      () => writeln("fun2")
    )
  ).doIt();
}

After compiling this code I expect to see the following output(or compiler
error, if I'm misusing lambda syntax):
fun1
fun2

Insted I get:
fun2

DMD64 D Compiler v2.060

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next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=8560


klickverbot <code klickverbot.at> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |code klickverbot.at
         Resolution|                            |INVALID


--- Comment #1 from klickverbot <code klickverbot.at> 2012-08-18 13:48:30 PDT
---
Marking as invalid, since {writeln("fun1");} is a parameterless delegate
literal. This delegate is returned by the call to fun(), but never invoked.

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prev sibling next sibling parent d-bugmail puremagic.com writes:
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--- Comment #2 from ilya <iu.biryukov gmail.com> 2012-08-18 13:55:08 PDT ---
(In reply to comment #1)

 Marking as invalid, since {writeln("fun1");} is a parameterless delegate
 literal. This delegate is returned by the call to fun(), but never invoked.


Thanks, now I get it.

Though this behavior looks a bit odd to me. But that's probably because of C#
background.

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prev sibling parent d-bugmail puremagic.com writes:
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--- Comment #3 from klickverbot <code klickverbot.at> 2012-08-18 13:57:54 PDT
---
(In reply to comment #2)

 Though this behavior looks a bit odd to me. But that's probably because of C#
 background.


Mhm, even if the current behavior is to spec, it can definitely be surprising.

If you feel something should be done about this, please consider starting a
discussion on the forums.

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