forked from jasder/antlr
91 lines
3.1 KiB
C#
91 lines
3.1 KiB
C#
/*
|
|
* [The "BSD license"]
|
|
* Copyright (c) 2013 Terence Parr
|
|
* Copyright (c) 2013 Sam Harwell
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
using Antlr4.Runtime;
|
|
using Antlr4.Runtime.Tree;
|
|
using Sharpen;
|
|
|
|
namespace Antlr4.Runtime.Tree
|
|
{
|
|
public class ParseTreeWalker
|
|
{
|
|
public static readonly ParseTreeWalker Default = new ParseTreeWalker();
|
|
|
|
public virtual void Walk(IParseTreeListener listener, IParseTree t)
|
|
{
|
|
if (t is IErrorNode)
|
|
{
|
|
listener.VisitErrorNode((IErrorNode)t);
|
|
return;
|
|
}
|
|
else
|
|
{
|
|
if (t is ITerminalNode)
|
|
{
|
|
listener.VisitTerminal((ITerminalNode)t);
|
|
return;
|
|
}
|
|
}
|
|
IRuleNode r = (IRuleNode)t;
|
|
EnterRule(listener, r);
|
|
int n = r.GetChildCount();
|
|
for (int i = 0; i < n; i++)
|
|
{
|
|
Walk(listener, r.GetChild(i));
|
|
}
|
|
ExitRule(listener, r);
|
|
}
|
|
|
|
/// <summary>
|
|
/// The discovery of a rule node, involves sending two events: the generic
|
|
/// <see cref="IParseTreeListener.EnterEveryRule(Antlr4.Runtime.ParserRuleContext)">IParseTreeListener.EnterEveryRule(Antlr4.Runtime.ParserRuleContext)
|
|
/// </see>
|
|
/// and a
|
|
/// <see cref="Antlr4.Runtime.RuleContext">Antlr4.Runtime.RuleContext</see>
|
|
/// -specific event. First we trigger the generic and then
|
|
/// the rule specific. We to them in reverse order upon finishing the node.
|
|
/// </summary>
|
|
protected internal virtual void EnterRule(IParseTreeListener listener, IRuleNode
|
|
r)
|
|
{
|
|
ParserRuleContext ctx = (ParserRuleContext)r.GetRuleContext();
|
|
listener.EnterEveryRule(ctx);
|
|
ctx.EnterRule(listener);
|
|
}
|
|
|
|
protected internal virtual void ExitRule(IParseTreeListener listener, IRuleNode r
|
|
)
|
|
{
|
|
ParserRuleContext ctx = (ParserRuleContext)r.GetRuleContext();
|
|
ctx.ExitRule(listener);
|
|
listener.ExitEveryRule(ctx);
|
|
}
|
|
}
|
|
}
|