1 /* 2 * [The "BSD licence"] 3 * Copyright (c) 2011 Terence Parr 4 * All rights reserved. 5 * 6 * Conversion to C#: 7 * Copyright (c) 2011 Sam Harwell, Pixel Mine, Inc. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 namespace Antlr.Runtime.Tree 34 { 35 36 /** <summary> 37 * A TreeAdaptor that works with any Tree implementation. It provides 38 * really just factory methods; all the work is done by BaseTreeAdaptor. 39 * If you would like to have different tokens created than ClassicToken 40 * objects, you need to override this and then set the parser tree adaptor to 41 * use your subclass. 42 * </summary> 43 * 44 * <remarks> 45 * To get your parser to build nodes of a different type, override 46 * create(Token), errorNode(), and to be safe, YourTreeClass.dupNode(). 47 * dupNode is called to duplicate nodes during rewrite operations. 48 * </remarks> 49 */ 50 public class CommonTreeAdaptor : BaseTreeAdaptor 51 { Create( IToken payload )52 public override object Create( IToken payload ) 53 { 54 return new CommonTree( payload ); 55 } 56 57 /** <summary> 58 * Tell me how to create a token for use with imaginary token nodes. 59 * For example, there is probably no input symbol associated with imaginary 60 * token DECL, but you need to create it as a payload or whatever for 61 * the DECL node as in ^(DECL type ID). 62 * </summary> 63 * 64 * <remarks> 65 * If you care what the token payload objects' type is, you should 66 * override this method and any other createToken variant. 67 * </remarks> 68 */ CreateToken( int tokenType, string text )69 public override IToken CreateToken( int tokenType, string text ) 70 { 71 return new CommonToken( tokenType, text ); 72 } 73 74 /** <summary> 75 * Tell me how to create a token for use with imaginary token nodes. 76 * For example, there is probably no input symbol associated with imaginary 77 * token DECL, but you need to create it as a payload or whatever for 78 * the DECL node as in ^(DECL type ID). 79 * </summary> 80 * 81 * <remarks> 82 * This is a variant of createToken where the new token is derived from 83 * an actual real input token. Typically this is for converting '{' 84 * tokens to BLOCK etc... You'll see 85 * 86 * r : lc='{' ID+ '}' -> ^(BLOCK[$lc] ID+) ; 87 * 88 * If you care what the token payload objects' type is, you should 89 * override this method and any other createToken variant. 90 * </remarks> 91 */ CreateToken( IToken fromToken )92 public override IToken CreateToken( IToken fromToken ) 93 { 94 return new CommonToken( fromToken ); 95 } 96 97 /** <summary> 98 * What is the Token associated with this node? If 99 * you are not using CommonTree, then you must 100 * override this in your own adaptor. 101 * </summary> 102 */ GetToken( object t )103 public override IToken GetToken( object t ) 104 { 105 if ( t is CommonTree ) 106 { 107 return ( (CommonTree)t ).Token; 108 } 109 return null; // no idea what to do 110 } 111 } 112 } 113