Type Function Tag [src]

Prototype

pub fn Tag(comptime T: type) type

Parameters

T: type

Example

 test Tag {
    const E = enum(u8) {
        C = 33,
        D,
    };
    const U = union(E) {
        C: u8,
        D: u16,
    };

    try testing.expect(Tag(E) == u8);
    try testing.expect(Tag(U) == E);
}

Source

  pub fn Tag(comptime T: type) type {
    return switch (@typeInfo(T)) {
        .@"enum" => |info| info.tag_type,
        .@"union" => |info| info.tag_type orelse @compileError(@typeName(T) ++ " has no tag type"),
        else => @compileError("expected enum or union type, found '" ++ @typeName(T) ++ "'"),
    };
}  