http://d.puremagic.com/issues/show_bug.cgi?id=586

           Summary: Cannot index tuple with non-type elements
           Product: D
           Version: 0.174
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla@digitalmars.com
        ReportedBy: kirklin.mcdonald@gmail.com


Take the following code:

template Tu(T ...) {
    alias T[1] Tu; // Line 2
}

void foo() { }

void main() {
    alias Tu!(real, int) T; // Works, no problem.
    alias Tu!(4, int) U;    // Results in error.
    alias Tu!(foo, int) V;  // Results in error.
    alias Tu!("a", int) W;  // Results in error.
}

The error in all three cases is:

test.d(2): tuple T is used as a type
test.d(X): template instance test.Tu!(<whatever>, int) error instantiating

Any tuple containing elements which are not types cannot be indexed. This limits certain kinds of advanced template code.

Bug 533 is a consequence of this bug. Bug 582 is essentially the same bug, but refers to slicing tuples rather than indexing them.


-- 

d-bugmail@puremagic.com schrieb am 2006-11-23:
> http://d.puremagic.com/issues/show_bug.cgi?id=586

> Take the following code:
>
> template Tu(T ...) {
>     alias T[1] Tu; // Line 2
> }
>
> void foo() { }
>
> void main() {
>     alias Tu!(real, int) T; // Works, no problem.
>     alias Tu!(4, int) U;    // Results in error.
>     alias Tu!(foo, int) V;  // Results in error.
>     alias Tu!("a", int) W;  // Results in error.
> }
>
> The error in all three cases is:
>
> test.d(2): tuple T is used as a type
> test.d(X): template instance test.Tu!(<whatever>, int) error instantiating
>
> Any tuple containing elements which are not types cannot be indexed. This limits certain kinds of advanced template code.
>
> Bug 533 is a consequence of this bug. Bug 582 is essentially the same bug, but refers to slicing tuples rather than indexing them.

Added to DStress as http://dstress.kuehne.cn/compile/t/tuple_04_A.d http://dstress.kuehne.cn/compile/t/tuple_04_B.d http://dstress.kuehne.cn/compile/t/tuple_04_C.d http://dstress.kuehne.cn/compile/t/tuple_04_D.d http://dstress.kuehne.cn/compile/t/tuple_04_E.d http://dstress.kuehne.cn/compile/t/tuple_04_F.d http://dstress.kuehne.cn/compile/t/tuple_04_G.d

Thomas

http://d.puremagic.com/issues/show_bug.cgi?id=586





------- Comment #2 from reiner.pope@gmail.com  2007-04-08 19:20 -------
This is even true for the perhaps simpler version, with a pure expression
tuple:
int F;

template A(T...)
{
    alias T[0] B; // Fails here
}

alias A!(F) C;

aliases.d(5): tuple T is used as a type
aliases.d(8): template instance aliases.A!(F) error instantiating


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=586


thomas-dloop@kuehne.cn changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         OS/Version|Windows                     |All




------- Comment #3 from thomas-dloop@kuehne.cn  2007-04-27 12:38 -------
Fixed DMD 1.013


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=586


bugzilla@digitalmars.com changed:

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




------- Comment #4 from bugzilla@digitalmars.com  2008-06-30 01:39 -------
Works in dmd 2.015 too.


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