Merge prolog.engine.create{,_and_ask} functions

1 files changed, 11 insertions, 16 deletions

diff --git a/prolog/engine.py b/prolog/engine.py
index 6215bb2..50282d4 100644
--- a/prolog/engine.py
+++ b/prolog/engine.py
@@ -6,27 +6,22 @@ import json
 import re
 import urllib
 
-# Create a new pengine, initialize it with [code] and return its ID. The engine
-# will be destroyed after completing one query.
-def create(code=''):
+# Create a new pengine, initialize it with [code] and return Prolog's reply.
+# The engine is destroyed after answering one query. If [query] is given, the
+# first answer is returned and the engine destroyed.
+def create(code='', query=''):
     opts = {'format': 'json-s', 'destroy': True, 'src_text': code}
+    if query:
+        opts['ask'] = query
     reply, messages = request('POST', '/pengine/create', body=json.dumps(opts))
 
     if reply.get('event') != 'create' or 'error' in messages:
         raise Exception('\n'.join(messages['error']))
 
-    return reply['id']
-
-# Create a new pengine with [code], run [query] and destroy the engine. Return
-# the reply from engine.
-def create_and_ask(code, query):
-    opts = {'format': 'json-s', 'destroy': True, 'src_text': code, 'ask': query}
-    reply, messages = request('POST', '/pengine/create', body=json.dumps(opts))
-
-    if reply.get('event') != 'create' or 'error' in messages:
-        raise Exception('\n'.join(messages['error']))
-
-    return reply['answer']['data']
+    # If query was given, the actual reply is nested in create/destroy objects.
+    if query:
+        reply = reply['answer']['data']
+    return reply
 
 def ask(engine, query):
     return send(engine, 'ask(({}),[])'.format(query))
@@ -107,7 +102,7 @@ def get_message(reply):
 
 # Basic sanity check.
 if __name__ == '__main__':
-    engine = create(code='dup([],[]). dup([H|T],[H,H|TT]) :- dup(T,TT).')
+    engine = create(code='dup([],[]). dup([H|T],[H,H|TT]) :- dup(T,TT).')['id']
     print('engine id is ' + engine)
     print(ask(engine, "run_tests({}, Result)".format('dup/2')))
     destroy(engine)