+ if ( length() >= str.length() )
+ {
+ // avoids a corner case later
+ if ( length() == 0 && str.length() == 0 )
+ return 0;
+
+ // "top" is the point where search starts from
+ size_t top = length() - str.length();
+
+ if ( nStart == npos )
+ nStart = length() - 1;
+ if ( nStart < top )
+ top = nStart;
+
+ const wxChar *cursor = c_str() + top;
+ do
+ {
+ if ( memcmp(cursor, str.c_str(),
+ str.length() * sizeof(wxChar)) == 0 )
+ {
+ return cursor - c_str();
+ }
+ } while ( cursor-- > c_str() );
+ }
+
+ return npos;