[Twisted-Python] Calling deferred within a callback, good or bad idea ?

[Stéphane Brault]

Hi,
 I have to call a web service then process the answer, according to the answer I may have to call the service again.
 The traditional way to go would be :
 condition = 1
 while condition:
     message = callWebService()
     condition = processMessage(message)
 
 Here is what I do :
 def function():
     
     def myCalback(message):
         condition = processMessage(message)
         if condition:
             deferred = callWebService()
              deferred.addCallback(myCallback)
 
     deferred = callWebService()
     deferred.addCallback(myCallback)
 
 I was wondering if it was the way to go or if there was a better way, since I'm not quite sure about the impact of calling new deffered within a callback.
 
 Thanks,
 
 Stéphane