Unknown state [2025-08-04]

glfw-vulkan/scratch/switch.zig

@@ -0,0 +1,42 @@
+const std = @import("std");
+
+const Data = enum { foo, bar };
+
+pub fn optional_enum_error_union() !?Data {
+    const state = struct {
+        var flag: u2 = 0;
+    };
+    defer state.flag +%= 1;
+
+    return switch (state.flag) {
+        0 => null,
+        1 => .foo,
+        2 => .bar,
+        3 => error.Fizz,
+    };
+}
+
+pub fn main() !void {
+    for (0..4) |_| {
+        const r1 = if (optional_enum_error_union()) |opt|
+            if (opt) |val|
+                switch (val) {
+                    .foo => "FOO",
+                    .bar => "BAR",
+                }
+            else
+                "NULL"
+        else |err| switch (err) {
+            error.Fizz => "FIZZ",
+            else => return err,
+        };
+
+        const r2 = switch (optional_enum_error_union()) {
+            .foo => "FOO",
+            .bar => "BAR",
+            null => "NULL",
+            error.Fizz => "FIZZ",
+            anyerror => |err| return err,
+        };
+    }
+}