44 lines
1 KiB
Zig
44 lines
1 KiB
Zig
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const std = @import("std");
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pub fn enumLiteral(comptime T: type) *const fn (value: []const u8) anyerror!T {
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const container = struct {
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fn func(value: []const u8) anyerror!T {
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return parseEnumFromStr(T, value);
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}
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};
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return &container.func;
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}
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fn parseEnumFromStr(comptime T: type, str: []const u8) !T {
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const info = @typeInfo(T);
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comptime {
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if (std.meta.activeTag(info) != .Enum) {
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@compileError("Expected enum type, got " ++ @typeName(T));
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}
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}
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inline for (info.Enum.fields) |field| {
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if (std.mem.eql(u8, field.name, str)) {
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return @enumFromInt(field.value);
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}
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}
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return error.InvalidEnum;
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}
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test "enum literal" {
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const t = std.testing;
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const Demo = enum(u8) {
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A,
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B,
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};
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try t.expectEqual(Demo.A, try parseEnumFromStr(Demo, "A"));
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try t.expectEqual(Demo.B, try parseEnumFromStr(Demo, "B"));
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try t.expectError(error.InvalidEnum, parseEnumFromStr(Demo, "DefinitelyNot"));
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}
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