gc: improved syntax errors

* example-based syntax errors (go.errors)

* enable bison's more specific errors
  and translate grammar token names into
  tokens like ++

* test cases

R=ken2, r, ken3
CC=golang-dev
http://codereview.appspot.com/194085

1 files changed, 14 insertions, 0 deletions

diff --git a/test/syntax/interface.go b/test/syntax/interface.go
new file mode 100644
index 000000000..a7f43533a
--- /dev/null
+++ b/test/syntax/interface.go
@@ -0,0 +1,14 @@
+// errchk $G -e $D/$F.go
+
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+type T interface {
+	f, g ()	// ERROR "name list not allowed in interface type"
+}
+
+
+