Function hasFn [src]

Returns true if a type has a namespace and the namespace contains name; false otherwise. Result is always comptime-known.

Prototype

pub inline fn hasFn(comptime T: type, comptime name: []const u8) bool

Parameters

T: typename: []const u8

Example

 test hasFn {
    const S1 = struct {
        pub fn foo() void {}
    };

    try std.testing.expect(hasFn(S1, "foo"));
    try std.testing.expect(!hasFn(S1, "bar"));
    try std.testing.expect(!hasFn(*S1, "foo"));

    const S2 = struct {
        foo: fn () void,
    };

    try std.testing.expect(!hasFn(S2, "foo"));
}

Source

  pub inline fn hasFn(comptime T: type, comptime name: []const u8) bool {
    switch (@typeInfo(T)) {
        .@"struct", .@"union", .@"enum", .@"opaque" => {},
        else => return false,
    }
    if (!@hasDecl(T, name))
        return false;

    return @typeInfo(@TypeOf(@field(T, name))) == .@"fn";
}  