http://d.puremagic.com/issues/show_bug.cgi?id=1006

           Summary: no ambiguity error given if getting function address
           Product: D
           Version: 1.007
          Platform: PC
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla@digitalmars.com
        ReportedBy: benoit@tionex.de


this compiles without error.
class C {
    void fnc(){
    }
    void fnc( int a ){
    }
    static this(){
        void* ptr = & fnc; //(1)
    }
}
I think (1) should be rejected, because of ambiguity.


-- 

d-bugmail@puremagic.com wrote:
> http://d.puremagic.com/issues/show_bug.cgi?id=1006
> 
>            Summary: no ambiguity error given if getting function address
>            Product: D
>            Version: 1.007
>           Platform: PC
>         OS/Version: Linux
>             Status: NEW
>           Severity: normal
>           Priority: P2
>          Component: DMD
>         AssignedTo: bugzilla@digitalmars.com
>         ReportedBy: benoit@tionex.de
> 
> 
> this compiles without error.
> class C {
>     void fnc(){
>     }
>     void fnc( int a ){
>     }
>     static this(){
>         void* ptr = & fnc; //(1)
>     }
> }
> I think (1) should be rejected, because of ambiguity.
> 
> 

This should not be made an error without adding a mechanism to get all of the overloads of a function, for example:

C.fnc.tupleof => Tuple!(void function(), void function(int))

-- 
Kirk McDonald
http://kirkmcdonald.blogspot.com
Pyd: Connecting D and Python
http://pyd.dsource.org

http://d.puremagic.com/issues/show_bug.cgi?id=1006


wbaxter@gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |wbaxter@gmail.com




------- Comment #2 from wbaxter@gmail.com  2007-02-24 15:31 -------
It's also very common to use overloads for properties.

void prop(int p) { return mProp=p; }
int prop() { return mProp; }

This is a problem for callback/sigslot mechanisms that very often want to call property-like functions.

   caller ~= (int x){ obj.prop=x; }
vs
   caller ~= &obj.prop;

The former introduces an extra layer of indirection, is slightly wordy, and is potentially problematic if 'obj' happens to go out of scope.  The latter is currently ambiguous.

Apparently a cast can be used currently:
   caller ~= cast(void function(int))&obj.prop;
but it is just too ugly.  And it's also semantically incorrect and unsafe.  I'm
not casting I'm trying to disambiguate.  And it's unsafe because the cast will
succeed even if obj.prop is a float* or anything else.

This is apparently an old proposal (according to Chris N-S) to disambiguate
without requiring a cast:
   caller ~= &obj.prop(int);

That would be great if that could be done without making the grammar ambiguous.

For generic programming purposes, this should also work:
   alias Tuple!(int) ArgTup;
   caller ~= &obj.prop(ArgTup);


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=1006





------- Comment #3 from wbaxter@gmail.com  2007-02-24 15:34 -------
I should add that the problem I spoke of exists only when 'caller.opCatAssign'
is a template that accepts multiple function/delegate signatures.
If its opCatAssign takes a particular signature then there's no problem.


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=1006


smjg@iname.com changed:

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




------- Comment #4 from smjg@iname.com  2007-02-25 10:32 -------


*** This bug has been marked as a duplicate of 52 ***


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