builtin: document true and false.
Fixes #5315.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8841048
diff --git a/src/pkg/builtin/builtin.go b/src/pkg/builtin/builtin.go
index d3c1a5c..128a1b5 100644
--- a/src/pkg/builtin/builtin.go
+++ b/src/pkg/builtin/builtin.go
@@ -13,6 +13,12 @@
// bool is the set of boolean values, true and false.
type bool bool
+// true and false are the two untyped boolean values.
+const (
+ true = 0 == 0 // Untyped bool.
+ false = 0 != 0 // Untyped bool.
+)
+
// uint8 is the set of all unsigned 8-bit integers.
// Range: 0 through 255.
type uint8 uint8
