02.09.2014 23:21, "Marc =?UTF-8?B?U2Now7x0eiI=?= <schue...@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)).
