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digitalmars.D.bugs - [Issue 9905] New: Template parameters used in argument delegate's arguments not inferred even if used and inferred previously in the function call

http://d.puremagic.com/issues/show_bug.cgi?id=9905

           Summary: Template parameters used in argument delegate's
                    arguments not inferred even if used and inferred
                    previously in the function call
           Product: D
           Version: D2
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: GenericNPC gmail.com
                CC: k.hara.pg gmail.com


--- Comment #0 from IdanArye <GenericNPC gmail.com> 2013-04-08 15:12:15 PDT ---
A simple example:

    void foo(T)(T a, void delegate(T) dlg){}

Calling it like this works:
    foo(1,(int x){});
    foo!int(1,(x){});

But trying to call it like this:
    foo(1,(x){});

Produces:
    main.d(8): Error: template main.foo does not match any function template
declaration. Candidates are:
    main.d(5):        main.foo(T)(T a, void delegate(T) dlg)
    main.d(8): Error: template main.foo(T)(T a, void delegate(T) dlg) cannot
deduce template function from argument types !()(int,void)

It seems that after reading the first argument `1` into `a`, the compiler knows
that `T` is `int`, but when it starts reading the second argument `(x){}` into
`dlg`, the compiler forgets that `T` is `int` and treats it as an unknown
template parameter.

Might be related to Issue 9393

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Apr 08 2013