go/doc: add IsPredeclared function

IsPredeclared allows simplifying src/golang.org/x/tools/godoc/linkify.go

Change-Id: I56b3223896f844630bc2e940255572d1682f0d06
Reviewed-on: https://go-review.googlesource.com/29870
Reviewed-by: Robert Griesemer <gri@golang.org>

diff --git a/src/go/doc/reader.go b/src/go/doc/reader.go
index e4e7b7c1c7db945e50fb8d4e9527bfef21426a82..c09f24d616adc8fac8d8a31de5d5f0e13e5f7021 100644 (file)
--- a/src/go/doc/reader.go
+++ b/src/go/doc/reader.go
@@ -809,6 +809,11 @@ func noteBodies(notes []*Note) []string {
 // ----------------------------------------------------------------------------
 // Predeclared identifiers
 
+// IsPredeclared reports whether s is a predeclared identifier.
+func IsPredeclared(s string) bool {
+       return predeclaredTypes[s] || predeclaredFuncs[s] || predeclaredConstants[s]
+}
+
 var predeclaredTypes = map[string]bool{
        "bool":       true,
        "byte":       true,