1// Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
2// Use of this file is governed by the BSD 3-clause license that
3// can be found in the LICENSE.txt file in the project root.
4
5package antlr
6
7import "fmt"
8
9type TraceListener struct {
10	parser *BaseParser
11}
12
13func NewTraceListener(parser *BaseParser) *TraceListener {
14	tl := new(TraceListener)
15	tl.parser = parser
16	return tl
17}
18
19func (t *TraceListener) VisitErrorNode(_ ErrorNode) {
20}
21
22func (t *TraceListener) EnterEveryRule(ctx ParserRuleContext) {
23	fmt.Println("enter   " + t.parser.GetRuleNames()[ctx.GetRuleIndex()] + ", LT(1)=" + t.parser.input.LT(1).GetText())
24}
25
26func (t *TraceListener) VisitTerminal(node TerminalNode) {
27	fmt.Println("consume " + fmt.Sprint(node.GetSymbol()) + " rule " + t.parser.GetRuleNames()[t.parser.ctx.GetRuleIndex()])
28}
29
30func (t *TraceListener) ExitEveryRule(ctx ParserRuleContext) {
31	fmt.Println("exit    " + t.parser.GetRuleNames()[ctx.GetRuleIndex()] + ", LT(1)=" + t.parser.input.LT(1).GetText())
32}
33