Added new example.

Updated ICU support for VC8


[SVN r37738]

example/snippets/partial_regex_iterate.cpp

@@ -0,0 +1,118 @@
+/*
+ *
+ * Copyright (c) 1998-2007
+ * John Maddock
+ *
+ * Use, modification and distribution are subject to the 
+ * Boost Software License, Version 1.0. (See accompanying file 
+ * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ *
+ */
+
+ /*
+  *   LOCATION:    see http://www.boost.org for most recent version.
+  *   FILE         partial_regex_iterate.cpp
+  *   VERSION      see <boost/version.hpp>
+  *   DESCRIPTION: Search example using partial matches.
+  */
+
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <string>
+#include <cstring>
+#include <boost/regex.hpp>
+
+#ifdef BOOST_NO_STDC_NAMESPACE
+namespace std{ using ::memmove; }
+#endif
+
+// match some kind of html tag:
+boost::regex e("<[^>]*>");
+// count how many:
+unsigned int tags = 0;
+
+void search(std::istream& is)
+{
+   // buffer we'll be searching in:
+   char buf[4096];
+   // saved position of end of partial match:
+   const char* next_pos = buf + sizeof(buf);
+   // flag to indicate whether there is more input to come:
+   bool have_more = true;
+
+   while(have_more)
+   {
+      // how much do we copy forward from last try:
+      unsigned leftover = (buf + sizeof(buf)) - next_pos;
+      // and how much is left to fill:
+      unsigned size = next_pos - buf;
+      // copy forward whatever we have left:
+      std::memmove(buf, next_pos, leftover);
+      // fill the rest from the stream:
+      is.read(buf + leftover, size);
+      unsigned read = is.gcount();
+      // check to see if we've run out of text:
+      have_more = read == size;
+      // reset next_pos:
+      next_pos = buf + sizeof(buf);
+      // and then iterate:
+      boost::cregex_iterator a(
+         buf, 
+         buf + read + leftover, 
+         e, 
+         boost::match_default | boost::match_partial); 
+      boost::cregex_iterator b;
+
+      while(a != b)
+      {
+         if((*a)[0].matched == false)
+         {
+            // Partial match, save position and break:
+            next_pos = (*a)[0].first;
+            break;
+         }
+         else
+         {
+            // full match:
+            ++tags;
+         }
+         
+         // move to next match:
+         ++a;
+      }
+   }
+}
+
+int main(int argc, char* argv[])
+{
+   if(argc > 1)
+   {
+      for(int i = 1; i < argc; ++i)
+      {
+         std::ifstream fs(argv[i]);
+         if(fs.bad()) continue;
+         search(fs);
+         fs.close();
+      }
+   }
+   else
+   {
+      std::string one("<META NAME=\"keywords\" CONTENT=\"regex++, regular expressions, regular expression library, C++\">");
+      std::string what;
+      while(what.size() < 10000)
+      {
+         what.append(one);
+         what.append(13, ' ');
+      }
+      std::stringstream ss;
+      ss.str(what);
+      search(ss);
+   }
+   std::cout << "total tag count was " << tags << std::endl;
+   return 0;
+}
+
+
+
+