Commit cea310c908

@@ -568,6 +568,33 @@ test "std.meta.fieldNames" {
     try testing.expectEqualSlices(u8, u1names[1], "b");
 }
 
+/// Given an enum or error set type, returns a pointer to an array containing all tags for that
+/// enum or error set.
+pub fn tags(comptime T: type) *const [fields(T).len]T {
+    comptime {
+        const fieldInfos = fields(T);
+        var res: [fieldInfos.len]T = undefined;
+        for (fieldInfos) |field, i| {
+            res[i] = @field(T, field.name);
+        }
+        return &res;
+    }
+}
+
+test "std.meta.tags" {
+    const E1 = enum { A, B };
+    const E2 = error{A};
+
+    const e1_tags = tags(E1);
+    const e2_tags = tags(E2);
+
+    try testing.expect(e1_tags.len == 2);
+    try testing.expectEqual(E1.A, e1_tags[0]);
+    try testing.expectEqual(E1.B, e1_tags[1]);
+    try testing.expect(e2_tags.len == 1);
+    try testing.expectEqual(E2.A, e2_tags[0]);
+}
+
 pub fn FieldEnum(comptime T: type) type {
     const field_infos = fields(T);
     var enumFields: [field_infos.len]std.builtin.Type.EnumField = undefined;

@@ -2,6 +2,7 @@ const std = @import("std");
 const fs = std.fs;
 const io = std.io;
 const mem = std.mem;
+const meta = std.meta;
 const Allocator = mem.Allocator;
 const Target = std.Target;
 const target = @import("target.zig");
@@ -35,27 +36,25 @@ pub fn cmdTargets(
 
     try jws.objectField("arch");
     try jws.beginArray();
-    {
-        inline for (@typeInfo(Target.Cpu.Arch).Enum.fields) |field| {
-            try jws.arrayElem();
-            try jws.emitString(field.name);
-        }
+    for (meta.fieldNames(Target.Cpu.Arch)) |field| {
+        try jws.arrayElem();
+        try jws.emitString(field);
     }
     try jws.endArray();
 
     try jws.objectField("os");
     try jws.beginArray();
-    inline for (@typeInfo(Target.Os.Tag).Enum.fields) |field| {
+    for (meta.fieldNames(Target.Os.Tag)) |field| {
         try jws.arrayElem();
-        try jws.emitString(field.name);
+        try jws.emitString(field);
     }
     try jws.endArray();
 
     try jws.objectField("abi");
     try jws.beginArray();
-    inline for (@typeInfo(Target.Abi).Enum.fields) |field| {
+    for (meta.fieldNames(Target.Abi)) |field| {
         try jws.arrayElem();
-        try jws.emitString(field.name);
+        try jws.emitString(field);
     }
     try jws.endArray();
 
@@ -84,10 +83,9 @@ pub fn cmdTargets(
 
     try jws.objectField("cpus");
     try jws.beginObject();
-    inline for (@typeInfo(Target.Cpu.Arch).Enum.fields) |field| {
-        try jws.objectField(field.name);
+    for (meta.tags(Target.Cpu.Arch)) |arch| {
+        try jws.objectField(@tagName(arch));
         try jws.beginObject();
-        const arch = @field(Target.Cpu.Arch, field.name);
         for (arch.allCpuModels()) |model| {
             try jws.objectField(model.name);
             try jws.beginArray();
@@ -105,10 +103,9 @@ pub fn cmdTargets(
 
     try jws.objectField("cpuFeatures");
     try jws.beginObject();
-    inline for (@typeInfo(Target.Cpu.Arch).Enum.fields) |field| {
-        try jws.objectField(field.name);
+    for (meta.tags(Target.Cpu.Arch)) |arch| {
+        try jws.objectField(@tagName(arch));
         try jws.beginArray();
-        const arch = @field(Target.Cpu.Arch, field.name);
         for (arch.allFeaturesList()) |feature| {
             try jws.arrayElem();
             try jws.emitString(feature.name);