1324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver/* 2324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * [The "BSD licence"] 3324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Copyright (c) 2005-2008 Terence Parr 4324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * All rights reserved. 5324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 6324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Conversion to C#: 7324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc. 8324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * All rights reserved. 9324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 10324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Redistribution and use in source and binary forms, with or without 11324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * modification, are permitted provided that the following conditions 12324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * are met: 13324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 1. Redistributions of source code must retain the above copyright 14324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * notice, this list of conditions and the following disclaimer. 15324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 2. Redistributions in binary form must reproduce the above copyright 16324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * notice, this list of conditions and the following disclaimer in the 17324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * documentation and/or other materials provided with the distribution. 18324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 3. The name of the author may not be used to endorse or promote products 19324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * derived from this software without specific prior written permission. 20324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 21324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver */ 32324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 33324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruvernamespace Antlr.Runtime.Tree { 34324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver using Console = System.Console; 35324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 36324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public class TreeRewriter<TTree> : TreeParser { 37324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver protected ITokenStream originalTokenStream; 38324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver protected ITreeAdaptor originalAdaptor; 39324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 40324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver System.Func<IAstRuleReturnScope<TTree>> topdown_func; 41324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver System.Func<IAstRuleReturnScope<TTree>> bottomup_func; 42324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 43324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public TreeRewriter(ITreeNodeStream input) 44324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver : this(input, new RecognizerSharedState()) { 45324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 46324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public TreeRewriter(ITreeNodeStream input, RecognizerSharedState state) 47324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver : base(input, state) { 48324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver originalAdaptor = input.TreeAdaptor; 49324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver originalTokenStream = input.TokenStream; 50324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver topdown_func = () => Topdown(); 51324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver bottomup_func = () => Bottomup(); 52324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 53324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 54324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public virtual object ApplyOnce(object t, System.Func<IAstRuleReturnScope<TTree>> whichRule) { 55324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if (t == null) 56324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return null; 57324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 58324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver try { 59324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver // share TreeParser object but not parsing-related state 60324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver state = new RecognizerSharedState(); 61324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver input = new CommonTreeNodeStream(originalAdaptor, t); 62324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver ((CommonTreeNodeStream)input).TokenStream = originalTokenStream; 63324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver BacktrackingLevel = 1; 64324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver IAstRuleReturnScope<TTree> r = whichRule(); 65324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver BacktrackingLevel = 0; 66324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if (Failed) 67324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return t; 68324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 69324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if (typeof(CommonTree).IsAssignableFrom(typeof(TTree))) { 70324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if (r != null && !t.Equals(r.Tree) && r.Tree != null) { 71324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver // show any transformations 72324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver Console.Out.WriteLine(((CommonTree)t).ToStringTree() + " -> " + 73324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver ((CommonTree)(object)r.Tree).ToStringTree()); 74324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 75324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 76324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 77324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if (r != null && r.Tree != null) 78324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return r.Tree; 79324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver else 80324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return t; 81324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } catch (RecognitionException) { 82324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 83324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return t; 84324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 85324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 86324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public virtual object ApplyRepeatedly(object t, System.Func<IAstRuleReturnScope<TTree>> whichRule) { 87324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver bool treeChanged = true; 88324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver while (treeChanged) { 89324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver object u = ApplyOnce(t, whichRule); 90324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver treeChanged = !t.Equals(u); 91324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver t = u; 92324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 93324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return t; 94324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 95324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 96324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public virtual object Downup(object t) { 97324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver TreeVisitor v = new TreeVisitor(new CommonTreeAdaptor()); 98324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver t = v.Visit(t, (o) => ApplyOnce(o, topdown_func), (o) => ApplyRepeatedly(o, bottomup_func)); 99324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return t; 100324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 101324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 102324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver // methods the downup strategy uses to do the up and down rules. 103324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver // to override, just define tree grammar rule topdown and turn on 104324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver // filter=true. 105324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public virtual IAstRuleReturnScope<TTree> Topdown() { 106324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return null; 107324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 108324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 109324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public virtual IAstRuleReturnScope<TTree> Bottomup() { 110324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver return null; 111324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 112324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 113324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver} 114