Function tagName [src]

A safe alternative to @tagName() for non-exhaustive enums that doesn't panic when e has no tagged value. Returns the tag name for e or null if no tag exists.

Prototype

pub fn tagName(comptime E: type, e: E) ?[:0]const u8

Parameters

E: typee: E

Example

 test tagName {
    const E = enum(u8) { a, b, _ };
    try testing.expect(tagName(E, .a) != null);
    try testing.expectEqualStrings("a", tagName(E, .a).?);
    try testing.expect(tagName(E, @as(E, @enumFromInt(42))) == null);
}

Source

  pub fn tagName(comptime E: type, e: E) ?[:0]const u8 {
    return inline for (@typeInfo(E).@"enum".fields) |f| {
        if (@intFromEnum(e) == f.value) break f.name;
    } else null;
}  