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digitalmars.D.bugs - [Issue 1464] New: "static" foreach breaks CTFE

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1464

           Summary: "static" foreach breaks CTFE
           Product: D
           Version: 2.003
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: reiner.pope gmail.com


The following code gives compile-time error, "cannot evaluate gen() at compile
time." Removing the "i" from the foreach fixes this.

template Tuple(T...)
{
        alias T val;
}

alias Tuple!(int) Tup;

string gen()
{
    foreach (i, type; Tup.val)
    {
    }
    return null;
}

string text = gen();


-- 
Aug 31 2007
next sibling parent reply BCS <BCS pathlink.com> writes:
d-bugmail puremagic.com wrote:
 http://d.puremagic.com/issues/show_bug.cgi?id=1464
 
            Summary: "static" foreach breaks CTFE
            Product: D
            Version: 2.003
           Platform: PC
         OS/Version: Windows
             Status: NEW
           Keywords: rejects-valid
           Severity: normal
           Priority: P2
          Component: DMD
         AssignedTo: bugzilla digitalmars.com
         ReportedBy: reiner.pope gmail.com
 
 
 The following code gives compile-time error, "cannot evaluate gen() at compile
 time." Removing the "i" from the foreach fixes this.
 
 template Tuple(T...)
 {
         alias T val;
 }
 
 alias Tuple!(int) Tup;
 
 string gen()
 {
     foreach (i, type; Tup.val)
     {
     }
     return null;
 }
 
 string text = gen();
 
 

That compiles at all? in the 1.x versions you can't have an alias of a tuple in a template other than if the tuple name is the same as the name of the template (It's a known bug, not a language restriction)
Aug 31 2007
parent reply Reiner Pope <some address.com> writes:
BCS wrote:
 d-bugmail puremagic.com wrote:
 http://d.puremagic.com/issues/show_bug.cgi?id=1464

            Summary: "static" foreach breaks CTFE
            Product: D
            Version: 2.003
           Platform: PC
         OS/Version: Windows
             Status: NEW
           Keywords: rejects-valid
           Severity: normal
           Priority: P2
          Component: DMD
         AssignedTo: bugzilla digitalmars.com
         ReportedBy: reiner.pope gmail.com


 The following code gives compile-time error, "cannot evaluate gen() at 
 compile
 time." Removing the "i" from the foreach fixes this.

 template Tuple(T...)
 {
         alias T val;
 }

 alias Tuple!(int) Tup;

 string gen()
 {
     foreach (i, type; Tup.val)
     {
     }
     return null;
 }

 string text = gen();

That compiles at all? in the 1.x versions you can't have an alias of a tuple in a template other than if the tuple name is the same as the name of the template (It's a known bug, not a language restriction)

It's aliasing the template instantiation, not the tuple. It should compile in 1.x as well as 2.x.
Aug 31 2007
parent BCS <BCS pathlink.com> writes:
Reiner Pope wrote:
 template Tuple(T...)
 {
         alias T val;
 }


It's aliasing the template instantiation, not the tuple. It should compile in 1.x as well as 2.x.

I'm looking at the above line. this is related to issues #1241 http://d.puremagic.com/issues/show_bug.cgi?id=1241 However I seem to remember that the problem is a bit more general than the fist listed case. Well I'll gave to revisit some of that.
Aug 31 2007
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1464


bugzilla digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED




------- Comment #2 from bugzilla digitalmars.com  2007-09-28 22:16 -------
Fixed dmd 1.021 and 2.004


-- 
Sep 28 2007