--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tango/tango/text/stream/RegexIterator.d	Fri Jan 11 17:57:40 2008 +0100
@@ -0,0 +1,103 @@
+/*******************************************************************************
+
+        copyright:      Copyright (c) 2004 Kris Bell. All rights reserved
+
+        license:        BSD style: $(LICENSE)
+
+        version:        Initial release: January 2006      
+        
+        author:         Kris
+
+*******************************************************************************/
+
+module tango.text.stream.RegexIterator;
+
+private import  tango.text.Regex;
+    
+private import  tango.text.stream.StreamIterator;
+
+/*******************************************************************************
+
+        Iterate across a set of text patterns.
+
+        Each pattern is exposed to the client as a slice of the original
+        content, where the slice is transient. If you need to retain the
+        exposed content, then you should .dup it appropriately. 
+
+        These iterators are based upon the IBuffer construct, and can
+        thus be used in conjunction with other Iterators and/or Reader
+        instances upon a common buffer ~ each will stay in lockstep via
+        state maintained within the IBuffer.
+
+        The content exposed via an iterator is supposed to be entirely
+        read-only. All current iterators abide by this rule, but it is
+        possible a user could mutate the content through a get() slice.
+        To enforce the desired read-only aspect, the code would have to 
+        introduce redundant copying or the compiler would have to support 
+        read-only arrays.
+
+        See LineIterator, SimpleIterator, RegexIterator, QuotedIterator.
+
+
+*******************************************************************************/
+
+class RegexIterator : StreamIterator!(char)
+{
+        private Regex regex;
+        private alias char T;
+        
+        /***********************************************************************
+        
+                Construct an uninitialized iterator. For example:
+                ---
+                auto lines = new LineIterator!(char);
+
+                void somefunc (IBuffer buffer)
+                {
+                        foreach (line; lines.set(buffer))
+                                 Cout (line).newline;
+                }
+                ---
+
+                Construct a streaming iterator upon a buffer:
+                ---
+                void somefunc (IBuffer buffer)
+                {
+                        foreach (line; new LineIterator!(char) (buffer))
+                                 Cout (line).newline;
+                }
+                ---
+                
+                Construct a streaming iterator upon a conduit:
+                ---
+                foreach (line; new LineIterator!(char) (new FileConduit ("myfile")))
+                         Cout (line).newline;
+                ---
+
+        ***********************************************************************/
+
+        this (T[] pattern, InputStream stream = null)
+        {
+                regex = new Regex (pattern, "");
+                super (stream);
+        }
+
+        /***********************************************************************
+                
+        ***********************************************************************/
+
+        protected uint scan (void[] data)
+        {
+                auto content = (cast(T*) data.ptr) [0 .. data.length / T.sizeof];
+
+                if (regex.test (content))
+                   {
+                   int start = regex.pmatch[0].rm_so;
+                   int finish = regex.pmatch[0].rm_eo;
+                   set (content.ptr, 0, start);
+                   return found (finish-1);        
+                   }
+
+                return notFound;
+        }
+}