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Alias `std.traits.FunctionTypeOf`

Get the function type from a callable object func, or from a function pointer/delegate type.


						
				alias FunctionTypeOf(alias func)
				 = Fsym;

Using builtin typeof on a property function yields the types of the property value, not of the property function itself. Still, FunctionTypeOf is able to obtain function types of properties.

Note

Do not confuse function types with function pointer types; function types are usually used for compile-time reflection purposes.

Example

class C
{
    int value() @property => 0;
    static string opCall() => "hi";
}
static assert(is( typeof(C.value) == int ));
static assert(is( FunctionTypeOf!(C.value) == function ));
static assert(is( FunctionTypeOf!C == typeof(C.opCall) ));

int function() fp;
alias IntFn = int();
static assert(is( typeof(fp) == IntFn* ));
static assert(is( FunctionTypeOf!fp == IntFn ));

Authors

Walter Bright, Tomasz Stachowiak (isExpressions), Andrei Alexandrescu, Shin Fujishiro, Robert Clipsham, David Nadlinger, Kenji Hara, Shoichi Kato

License

Boost License 1.0.