Enum member hasFunctionMember

Returns true if a type has a function member

enum hasFunctionMember(T, string name) = isFunction!(__traits(getMember, T, name));

Example

static struct S {
    int i;
    void f0() {}
    int f1(int, int) { return 0; }
    static void f2(string) {}
    static int s;
}

static assert(!hasFunctionMember!(S, "i"));
static assert( hasFunctionMember!(S, "f0"));
static assert( hasFunctionMember!(S, "f1"));
static assert( hasFunctionMember!(S, "f2"));
static assert(!hasFunctionMember!(S, "s"));