[message filter]

- take filter string and substite string
- can now replace key by another key

git-svn-id: http://moon:8086/svn/software/trunk/projects/GnuRadio@529 b431acfa-c32f-4a4a-93f1-934dc6c82436

gr-jay/python/message_filter.py

@@ -27,13 +27,14 @@ class message_filter(gr.basic_block):
     """
     docstring for block message_filter
     """
-    def __init__(self, filter='freq'):
+    def __init__(self, filter, subst=''):
         gr.basic_block.__init__(self,
             name="message_filter",
             in_sig=None,
             out_sig=None)
 
         self.filter = filter
+        self.subst = subst
 
         # Register in / out message ports
         self.port_in = pmt.intern("in")
@@ -47,9 +48,13 @@ class message_filter(gr.basic_block):
 
     def delegate_pair(self, pair):
         key = pmt.car(pair)
+        val = pmt.cdr(pair)
         key_str = pmt.symbol_to_string(key)
 
         if self.filter in key_str:
+            if len(self.subst):
+                pair = pmt.cons(pmt.string_to_symbol(self.subst), val)
+
             self.message_port_pub(self.port_out, pair)
 
     def msg_handler(self, msg):