diff --git a/src/pkg/html/template/template.go b/src/pkg/html/template/template.go
index 768cee7d5f..e183898d50 100644
--- a/src/pkg/html/template/template.go
+++ b/src/pkg/html/template/template.go
@@ -45,18 +45,24 @@ func (t *Template) Templates() []*Template {
 	return m
 }
 
+// escape escapes all associated templates.
+func (t *Template) escape() error {
+	t.nameSpace.mu.Lock()
+	defer t.nameSpace.mu.Unlock()
+	if !t.escaped {
+		if err := escapeTemplates(t, t.Name()); err != nil {
+			return err
+		}
+		t.escaped = true
+	}
+	return nil
+}
+
 // Execute applies a parsed template to the specified data object,
 // writing the output to wr.
-func (t *Template) Execute(wr io.Writer, data interface{}) (err error) {
-	t.nameSpace.mu.Lock()
-	if !t.escaped {
-		if err = escapeTemplates(t, t.Name()); err != nil {
-			t.escaped = true
-		}
-	}
-	t.nameSpace.mu.Unlock()
-	if err != nil {
-		return
+func (t *Template) Execute(wr io.Writer, data interface{}) error {
+	if err := t.escape(); err != nil {
+		return err
 	}
 	return t.text.Execute(wr, data)
 }