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digitalmars.D.bugs - [Issue 1241] New: ICE on template instance parameter

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1241

           Summary: ICE on template instance parameter
           Product: D
           Version: 1.014
          Platform: PC
        OS/Version: All
            Status: NEW
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: manuelk89 gmx.net


The following template instance parameter crashes dmd when the parameter gets
accessed:


template List(L...)
{
        alias L get;
}

template Foo(alias A)
{
        int len1 = A.get.length; // access causes ICE
}

void main()
{
        alias Foo!(List!(1,2,3)) foo; // instance parameter is List!(1,2,3)
}

-------------------------------
compile session:

$ dmd main.d
dmd: expression.c:4729: virtual Expression* DotIdExp::semantic(Scope*):
Assertion `0' failed.
Aborted (core dumped)

---

PS: when this gets fixed there is a nice way to pass more than one Tuple to a
template by just passing several template instances that carry the tuples in
them (just as the List template above).


--
May 18 2007
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1241


onlystupidspamhere yahoo.se changed:

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







*** This bug has been marked as a duplicate of 911 ***


--
Jun 23 2007
prev sibling parent reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1241


shro8822 vandals.uidaho.edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |shro8822 vandals.uidaho.edu





I have also run into this one. I was trying to use the tuples+templates as
compile time trees

template Foo(A...)
{
  template Bar(B...)
  {
    alias A a;
    alias B b;
  }
}

alias Foo!(Foo!(1,2,3).Bar!(4,5,6)).Bar!(Foo!(7,8,9).Bar!(10,11,12)) tree;

foreach( a; tree.a)
{
  foreach(aa; a.a);
  foreach(ab; a.b);
}
foreach( b; tree.b)
{
  foreach(ba; b.a);
  foreach(bb; b.b);
}

Can we please get a fix on this one? It will drop a LOT of barriers to
elaborate template systems. I have a few really cool things that use it and
would like to put them in my talk without the disclaimer of "this would work



--
Jul 22 2007
parent =?ISO-8859-1?Q?Manuel_K=F6nig?= <ManuelK89 gmx.net> writes:
d-bugmail puremagic.com wrote:

 http://d.puremagic.com/issues/show_bug.cgi?id=1241
 
 
 shro8822 vandals.uidaho.edu changed:
 
            What    |Removed                     |Added
 ----------------------------------------------------------------------------
                  CC|                            |shro8822 vandals.uidaho.edu
 
 
 
 

 I have also run into this one. I was trying to use the tuples+templates as
 compile time trees
 
 template Foo(A...)
 {
   template Bar(B...)
   {
     alias A a;
     alias B b;
   }
 }
 
 alias Foo!(Foo!(1,2,3).Bar!(4,5,6)).Bar!(Foo!(7,8,9).Bar!(10,11,12)) tree;
 
 foreach( a; tree.a)
 {
   foreach(aa; a.a);
   foreach(ab; a.b);
 }
 foreach( b; tree.b)
 {
   foreach(ba; b.a);
   foreach(bb; b.b);
 }
 
 Can we please get a fix on this one? It will drop a LOT of barriers to
 elaborate template systems. I have a few really cool things that use it and
 would like to put them in my talk without the disclaimer of "this would work

 
 


I just discovered a decent workaround. Instead of using templates with 
tuple members, just use structs:

Use

struct Tuple(T...)
{
	alias T tp;
}

instead of

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

I tested this with dmd1.020 and rewrote your tree structure using this 
trick:

import std.stdio;

struct Foo(A...)
{
   struct Bar(B...)
   {
     alias A a;
     alias B b;
   }
}

alias Foo!(Foo!(1,2,3).Bar!(4,5,6)).Bar!(Foo!(7,8,9).Bar!(10,11,12)) tree;

void main()
{
	foreach( a; tree.a)
	{
	  foreach(aa; a.a) writefln(aa);
	  foreach(ab; a.b) writefln(ab);
	}
	foreach( b; tree.b)
	{
	  foreach(ba; b.a) writefln(ba);
	  foreach(bb; b.b) writefln(bb);
	}
}

This prints
1
2
3
4
5
6
7
8
9
10
11
12

for me. Happy coding!
Aug 01 2007