/*
* [The "BSD licence"]
* Copyright (c) 2005-2008 Terence Parr
* All rights reserved.
*
* Conversion to C#:
* Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc.
* 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.
*/
namespace Antlr.Runtime.Tree {
/** <summary>
* A TreeAdaptor that works with any Tree implementation. It provides
* really just factory methods; all the work is done by BaseTreeAdaptor.
* If you would like to have different tokens created than ClassicToken
* objects, you need to override this and then set the parser tree adaptor to
* use your subclass.
* </summary>
*
* <remarks>
* To get your parser to build nodes of a different type, override
* create(Token), errorNode(), and to be safe, YourTreeClass.dupNode().
* dupNode is called to duplicate nodes during rewrite operations.
* </remarks>
*/
public class CommonTreeAdaptor : BaseTreeAdaptor {
/** <summary>
* Duplicate a node. This is part of the factory;
* override if you want another kind of node to be built.
* </summary>
*
* <remarks>
* I could use reflection to prevent having to override this
* but reflection is slow.
* </remarks>
*/
public override object DupNode(object t) {
if (t == null)
return null;
return ((ITree)t).DupNode();
}
public override object Create(IToken payload) {
return new CommonTree(payload);
}
/** <summary>
* Tell me how to create a token for use with imaginary token nodes.
* For example, there is probably no input symbol associated with imaginary
* token DECL, but you need to create it as a payload or whatever for
* the DECL node as in ^(DECL type ID).
* </summary>
*
* <remarks>
* If you care what the token payload objects' type is, you should
* override this method and any other createToken variant.
* </remarks>
*/
public override IToken CreateToken(int tokenType, string text) {
return new CommonToken(tokenType, text);
}
/** <summary>
* Tell me how to create a token for use with imaginary token nodes.
* For example, there is probably no input symbol associated with imaginary
* token DECL, but you need to create it as a payload or whatever for
* the DECL node as in ^(DECL type ID).
* </summary>
*
* <remarks>
* This is a variant of createToken where the new token is derived from
* an actual real input token. Typically this is for converting '{'
* tokens to BLOCK etc... You'll see
*
* r : lc='{' ID+ '}' -> ^(BLOCK[$lc] ID+) ;
*
* If you care what the token payload objects' type is, you should
* override this method and any other createToken variant.
* </remarks>
*/
public override IToken CreateToken(IToken fromToken) {
return new CommonToken(fromToken);
}
/** <summary>
* Track start/stop token for subtree root created for a rule.
* Only works with Tree nodes. For rules that match nothing,
* seems like this will yield start=i and stop=i-1 in a nil node.
* Might be useful info so I'll not force to be i..i.
* </summary>
*/
public override void SetTokenBoundaries(object t, IToken startToken, IToken stopToken) {
if (t == null)
return;
int start = 0;
int stop = 0;
if (startToken != null)
start = startToken.TokenIndex;
if (stopToken != null)
stop = stopToken.TokenIndex;
((ITree)t).TokenStartIndex = start;
((ITree)t).TokenStopIndex = stop;
}
public override int GetTokenStartIndex(object t) {
if (t == null)
return -1;
return ((ITree)t).TokenStartIndex;
}
public override int GetTokenStopIndex(object t) {
if (t == null)
return -1;
return ((ITree)t).TokenStopIndex;
}
public override string GetText(object t) {
if (t == null)
return null;
return ((ITree)t).Text;
}
public override int GetType(object t) {
if (t == null)
return TokenTypes.Invalid;
return ((ITree)t).Type;
}
/** <summary>
* What is the Token associated with this node? If
* you are not using CommonTree, then you must
* override this in your own adaptor.
* </summary>
*/
public override IToken GetToken(object t) {
if (t is CommonTree) {
return ((CommonTree)t).Token;
}
return null; // no idea what to do
}
public override object GetChild(object t, int i) {
if (t == null)
return null;
return ((ITree)t).GetChild(i);
}
public override int GetChildCount(object t) {
if (t == null)
return 0;
return ((ITree)t).ChildCount;
}
public override object GetParent(object t) {
if (t == null)
return null;
return ((ITree)t).Parent;
}
public override void SetParent(object t, object parent) {
if (t != null)
((ITree)t).Parent = (ITree)parent;
}
public override int GetChildIndex(object t) {
if (t == null)
return 0;
return ((ITree)t).ChildIndex;
}
public override void SetChildIndex(object t, int index) {
if (t != null)
((ITree)t).ChildIndex = index;
}
public override void ReplaceChildren(object parent, int startChildIndex, int stopChildIndex, object t) {
if (parent != null) {
((ITree)parent).ReplaceChildren(startChildIndex, stopChildIndex, t);
}
}
}
}