| /* |
| * [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 |
| { |
| using IList = System.Collections.IList; |
| |
| [System.Serializable] |
| public class RewriteRuleSubtreeStream : RewriteRuleElementStream |
| { |
| public RewriteRuleSubtreeStream( ITreeAdaptor adaptor, string elementDescription ) |
| : base( adaptor, elementDescription ) |
| { |
| } |
| |
| /** <summary>Create a stream with one element</summary> */ |
| public RewriteRuleSubtreeStream( ITreeAdaptor adaptor, string elementDescription, object oneElement ) |
| : base( adaptor, elementDescription, oneElement ) |
| { |
| } |
| |
| /** <summary>Create a stream, but feed off an existing list</summary> */ |
| public RewriteRuleSubtreeStream( ITreeAdaptor adaptor, string elementDescription, IList elements ) |
| : base( adaptor, elementDescription, elements ) |
| { |
| } |
| |
| /** <summary> |
| * Treat next element as a single node even if it's a subtree. |
| * This is used instead of next() when the result has to be a |
| * tree root node. Also prevents us from duplicating recently-added |
| * children; e.g., ^(type ID)+ adds ID to type and then 2nd iteration |
| * must dup the type node, but ID has been added. |
| * </summary> |
| * |
| * <remarks> |
| * Referencing a rule result twice is ok; dup entire tree as |
| * we can't be adding trees as root; e.g., expr expr. |
| * |
| * Hideous code duplication here with super.next(). Can't think of |
| * a proper way to refactor. This needs to always call dup node |
| * and super.next() doesn't know which to call: dup node or dup tree. |
| * </remarks> |
| */ |
| public virtual object NextNode() |
| { |
| //System.Console.WriteLine("nextNode: elements={0}, singleElement={1}", elements, ((ITree)singleElement).ToStringTree()); |
| int n = Count; |
| if ( dirty || ( cursor >= n && n == 1 ) ) |
| { |
| // if out of elements and size is 1, dup (at most a single node |
| // since this is for making root nodes). |
| object el = NextCore(); |
| return adaptor.DupNode( el ); |
| } |
| // test size above then fetch |
| object tree = NextCore(); |
| while (adaptor.IsNil(tree) && adaptor.GetChildCount(tree) == 1) |
| tree = adaptor.GetChild(tree, 0); |
| //System.Console.WriteLine("_next={0}", ((ITree)tree).ToStringTree()); |
| object el2 = adaptor.DupNode(tree); // dup just the root (want node here) |
| return el2; |
| } |
| |
| protected override object Dup( object el ) |
| { |
| return adaptor.DupTree( el ); |
| } |
| } |
| } |