1 files changed, 162 insertions, 0 deletions
diff --git a/runtime/CSharp3/Sources/Antlr3.Runtime/Tree/TreePatternLexer.cs b/runtime/CSharp3/Sources/Antlr3.Runtime/Tree/TreePatternLexer.cs
new file mode 100644
index 0000000..e742205
--- /dev/null
+++ b/runtime/CSharp3/Sources/Antlr3.Runtime/Tree/TreePatternLexer.cs
@@ -0,0 +1,162 @@
+/*
+ * [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 StringBuilder = System.Text.StringBuilder;
+
+    public class TreePatternLexer
+    {
+        public const int Begin = 1;
+        public const int End = 2;
+        public const int Id = 3;
+        public const int Arg = 4;
+        public const int Percent = 5;
+        public const int Colon = 6;
+        public const int Dot = 7;
+
+        /** <summary>The tree pattern to lex like "(A B C)"</summary> */
+        protected string pattern;
+
+        /** <summary>Index into input string</summary> */
+        protected int p = -1;
+
+        /** <summary>Current char</summary> */
+        protected int c;
+
+        /** <summary>How long is the pattern in char?</summary> */
+        protected int n;
+
+        /** <summary>Set when token type is ID or ARG (name mimics Java's StreamTokenizer)</summary> */
+        public StringBuilder sval = new StringBuilder();
+
+        public bool error = false;
+
+        public TreePatternLexer( string pattern )
+        {
+            this.pattern = pattern;
+            this.n = pattern.Length;
+            Consume();
+        }
+
+        public virtual int NextToken()
+        {
+            sval.Length = 0; // reset, but reuse buffer
+            while ( c != CharStreamConstants.EndOfFile )
+            {
+                if ( c == ' ' || c == '\n' || c == '\r' || c == '\t' )
+                {
+                    Consume();
+                    continue;
+                }
+                if ( ( c >= 'a' && c <= 'z' ) || ( c >= 'A' && c <= 'Z' ) || c == '_' )
+                {
+                    sval.Append( (char)c );
+                    Consume();
+                    while ( ( c >= 'a' && c <= 'z' ) || ( c >= 'A' && c <= 'Z' ) ||
+                            ( c >= '0' && c <= '9' ) || c == '_' )
+                    {
+                        sval.Append( (char)c );
+                        Consume();
+                    }
+                    return Id;
+                }
+                if ( c == '(' )
+                {
+                    Consume();
+                    return Begin;
+                }
+                if ( c == ')' )
+                {
+                    Consume();
+                    return End;
+                }
+                if ( c == '%' )
+                {
+                    Consume();
+                    return Percent;
+                }
+                if ( c == ':' )
+                {
+                    Consume();
+                    return Colon;
+                }
+                if ( c == '.' )
+                {
+                    Consume();
+                    return Dot;
+                }
+                if ( c == '[' )
+                {
+                    // grab [x] as a string, returning x
+                    Consume();
+                    while ( c != ']' )
+                    {
+                        if ( c == '\\' )
+                        {
+                            Consume();
+                            if ( c != ']' )
+                            {
+                                sval.Append( '\\' );
+                            }
+                            sval.Append( (char)c );
+                        }
+                        else
+                        {
+                            sval.Append( (char)c );
+                        }
+                        Consume();
+                    }
+                    Consume();
+                    return Arg;
+                }
+                Consume();
+                error = true;
+                return CharStreamConstants.EndOfFile;
+            }
+            return CharStreamConstants.EndOfFile;
+        }
+
+        protected virtual void Consume()
+        {
+            p++;
+            if ( p >= n )
+            {
+                c = CharStreamConstants.EndOfFile;
+            }
+            else
+            {
+                c = pattern[p];
+            }
+        }
+    }
+}