Home | History | Annotate | Download | only in Tree 
      1 /*
      2  * [The "BSD licence"]
      3  * Copyright (c) 2005-2008 Terence Parr
      4  * All rights reserved.
      5  *
      6  * Conversion to C#:
      7  * Copyright (c) 2008-2009 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     using System.Collections.Generic;
     36 
     37     using StringBuilder = System.Text.StringBuilder;
     38 
     39     /** <summary>
     40      *  A record of the rules used to match a token sequence.  The tokens
     41      *  end up as the leaves of this tree and rule nodes are the interior nodes.
     42      *  This really adds no functionality, it is just an alias for CommonTree
     43      *  that is more meaningful (specific) and holds a String to display for a node.
     44      *  </summary>
     45      */
     46     [System.Serializable]
     47     public class ParseTree : BaseTree
     48     {
     49         public object payload;
     50         public List<IToken> hiddenTokens;
     51 
     52         public ParseTree( object label )
     53         {
     54             this.payload = label;
     55         }
     56 
     57         #region Properties
     58         public override string Text
     59         {
     60             get
     61             {
     62                 return ToString();
     63             }
     64             set
     65             {
     66             }
     67         }
     68         public override int TokenStartIndex
     69         {
     70             get
     71             {
     72                 return 0;
     73             }
     74             set
     75             {
     76             }
     77         }
     78         public override int TokenStopIndex
     79         {
     80             get
     81             {
     82                 return 0;
     83             }
     84             set
     85             {
     86             }
     87         }
     88         public override int Type
     89         {
     90             get
     91             {
     92                 return 0;
     93             }
     94             set
     95             {
     96             }
     97         }
     98         #endregion
     99 
    100         public override ITree DupNode()
    101         {
    102             return null;
    103         }
    104 
    105         public override string ToString()
    106         {
    107             if ( payload is IToken )
    108             {
    109                 IToken t = (IToken)payload;
    110                 if ( t.Type == TokenTypes.EndOfFile )
    111                 {
    112                     return "<EOF>";
    113                 }
    114                 return t.Text;
    115             }
    116             return payload.ToString();
    117         }
    118 
    119         /** <summary>
    120          *  Emit a token and all hidden nodes before.  EOF node holds all
    121          *  hidden tokens after last real token.
    122          *  </summary>
    123          */
    124         public virtual string ToStringWithHiddenTokens()
    125         {
    126             StringBuilder buf = new StringBuilder();
    127             if ( hiddenTokens != null )
    128             {
    129                 for ( int i = 0; i < hiddenTokens.Count; i++ )
    130                 {
    131                     IToken hidden = (IToken)hiddenTokens[i];
    132                     buf.Append( hidden.Text );
    133                 }
    134             }
    135             string nodeText = this.ToString();
    136             if ( !nodeText.Equals( "<EOF>" ) )
    137                 buf.Append( nodeText );
    138             return buf.ToString();
    139         }
    140 
    141         /** <summary>
    142          *  Print out the leaves of this tree, which means printing original
    143          *  input back out.
    144          *  </summary>
    145          */
    146         public virtual string ToInputString()
    147         {
    148             StringBuilder buf = new StringBuilder();
    149             ToStringLeaves( buf );
    150             return buf.ToString();
    151         }
    152 
    153         protected virtual void ToStringLeaves( StringBuilder buf )
    154         {
    155             if ( payload is IToken )
    156             { // leaf node token?
    157                 buf.Append( this.ToStringWithHiddenTokens() );
    158                 return;
    159             }
    160             for ( int i = 0; Children != null && i < Children.Count; i++ )
    161             {
    162                 ParseTree t = (ParseTree)Children[i];
    163                 t.ToStringLeaves( buf );
    164             }
    165         }
    166     }
    167 }
    168