Add ParseFile convenience method

parser/tree.go

@@ -59,3 +59,11 @@ func (this *Tree) Parse (name string, file io.Reader) error {
 	this.Declarations = append(this.Declarations, parsed.Declarations...)
 	return err
 }
+
+// ParseFile parses the contents of the given file into the tree.
+func (this *Tree) ParseFile (name string) error {
+	file, err := os.Open(name)
+	if err != nil { return err }
+	defer file.Close()
+	return this.Parse(name, file)
+}