Struct constructors and opCall

[Jarrett Billingsley]

On Tue, Mar 17, 2009 at 10:23 PM, Gide Nwawudu <gide at btinternet.com> wrote:
> On Tue, 17 Mar 2009 11:59:42 +0100, Lars Kyllingstad
> <public at kyllingen.NOSPAMnet> wrote:
>
>>I've come across the following strange behaviour in D2. Consider a
>>struct with a constructor, static opCall and non-static opCall:
>>
>>     import std.stdio;
>>
>>     struct Foo
>>     {
>>         this(int i)               { writefln("constructor"); }
>>         static void opCall(int i) { writefln("static opCall"); }
>>         void opCall(int i)        { writefln("instance opCall"); }
>>     }
>>
>>     void main()
>>     {
>>         auto foo = Foo(1);
>>         Foo(1);
>>         foo(1);
>>     }
>>
>>I expected that either compilation should fail because of ambiguity, or
>>the program should compile and run with the following output:
>>
>>     constructor
>>     static opCall
>>     instance opCall
>>
>>Instead, compiled with the newest DMD (2.026), it prints
>>
>>     constructor
>>     constructor
>>     constructor
>>
>>This has to be a bug. Is it a known one? I tried searching for "struct
>>constructor opCall" in both Bugzilla and Google, but couldn't find anything.
>>
>>-Lars
>
>
> http://www.digitalmars.com/d/archives/digitalmars/D/announce/DMD_1.035_and_2.019_releases_12806.html#N12833
>
> Walter wrote:
> "If there's any constructor defined for S, then S(args) is a
> constructor call.
>
> If there's any opCall defined for S, then S(args) is an opCall call.
>
> Otherwise, it's a struct literal."

foo(1) calling the constructor is almost certainly a bug, though.  It
really should call the instance opCall.