• Ivan Timokhin (17/17) Sep 02 2014 Is it possible to get all overloads of an operator for a particular type...
• "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> (6/25) Sep 02 2014 I can't answer the question about inspecting the overloads, but
• Ivan Timokhin (5/33) Sep 03 2014 Thanks for the answer, but I what I want is not to know whether it

Ivan Timokhin <timokhin.iv gmail.com> writes:

Is it possible to get all overloads of an operator for a particular type?

I.e., having this struct definition, is it possible to tell at compile 
time that it can be added with double and int[]?

struct S
{
     void opBinary(string op : "+")(double);
     void opBinary(string op : "+")(int[]);
}

To clarify, I am well aware that it can also be overloaded through the 
second argument via opBinaryRight, but for now I'm only interested in 
overloads provided by S itself.

I've tried __traits(getOverloads), but with no success: 
__traits(getOverloads, S, "opBinary") returns empty tuple,
and __traits(getOverloads, S, `opBinary!"+"`) results in a compilation
error (dmd 2.065):

Error: no property 'opBinary!"+"' for type 'S'
Error: (S).opBinary!"+" cannot be resolved

"Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:

On Tuesday, 2 September 2014 at 18:55:50 UTC, Ivan Timokhin wrote:
 Is it possible to get all overloads of an operator for a 
 particular type?

 I.e., having this struct definition, is it possible to tell at 
 compile time that it can be added with double and int[]?

 struct S
 {
     void opBinary(string op : "+")(double);
     void opBinary(string op : "+")(int[]);
 }

 To clarify, I am well aware that it can also be overloaded 
 through the second argument via opBinaryRight, but for now I'm 
 only interested in overloads provided by S itself.

 I've tried __traits(getOverloads), but with no success: 
 __traits(getOverloads, S, "opBinary") returns empty tuple,
 and __traits(getOverloads, S, `opBinary!"+"`) results in a 
 compilation
 error (dmd 2.065):

 Error: no property 'opBinary!"+"' for type 'S'
 Error: (S).opBinary!"+" cannot be resolved

I can't answer the question about inspecting the overloads, but 
if you just want to know whether it supports addition, the 
idiomatic way is to test whether it compiles:

     enum supportsAddition(S) = is(typeof(S.init + 0.0));

     static if(supportsAddition!MyType) { ... }

Ivan Timokhin <timokhin.iv gmail.com> writes:

02.09.2014 23:21, "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net>" пишет:
 On Tuesday, 2 September 2014 at 18:55:50 UTC, Ivan Timokhin wrote:
 Is it possible to get all overloads of an operator for a particular type?

 I.e., having this struct definition, is it possible to tell at compile
 time that it can be added with double and int[]?

 struct S
 {
     void opBinary(string op : "+")(double);
     void opBinary(string op : "+")(int[]);
 }

 To clarify, I am well aware that it can also be overloaded through the
 second argument via opBinaryRight, but for now I'm only interested in
 overloads provided by S itself.

 I've tried __traits(getOverloads), but with no success:
 __traits(getOverloads, S, "opBinary") returns empty tuple,
 and __traits(getOverloads, S, `opBinary!"+"`) results in a compilation
 error (dmd 2.065):

 Error: no property 'opBinary!"+"' for type 'S'
 Error: (S).opBinary!"+" cannot be resolved

 I can't answer the question about inspecting the overloads, but if you
 just want to know whether it supports addition, the idiomatic way is to
 test whether it compiles:

      enum supportsAddition(S) = is(typeof(S.init + 0.0));

      static if(supportsAddition!MyType) { ... }

Thanks for the answer, but I what I want is not to know whether it 
supports addition with some particular type, but to list all types that 
are supported (at least explicitly, ignoring templates like 
opBinary(string op, T)(T)).