test:zig

guide/language/labelled-blocks.zig

@@ -0,0 +1,24 @@
+const expect = @import("std").testing.expect;
+
+// Blocks in Zig are expressions and can be given labels, which are used to yield values.
+// Here, we are using a label called `blk`.
+// Blocks yield values, meaning they can be used in place of a value.
+// The value of an empty block `{}` is a value of the type `void`.
+
+test "labelled blocks" {
+    const count = blk: {
+        var sum: u32 = 0;
+        var i: u32 = 0;
+        while (i < 10) : (i += 1) sum += i;
+        break :blk sum;
+    };
+    try expect(count == 45);
+    try expect(@TypeOf(count) == u32);
+}
+
+// This can be seen as being equivalent to C's `i++`.
+// blk: {
+//     const tmp = i;
+//     i += 1;
+//     break :blk tmp;
+// }