draft of coroutine examples

control/adder/coroadder.py

@@ -45,7 +45,7 @@ Result = collections.namedtuple('Result', 'sum terms average')
 
 def adder_coro(initial=0):
     total = initial
-    num_terms = 0
+    count = 0
     while True:
         try:
             term = yield total
@@ -54,8 +54,8 @@ def adder_coro(initial=0):
         if term is None:
             break
         total += term
-        num_terms += 1
-    return Result(total, num_terms, total/num_terms)
+        count += 1
+    return Result(total, count, total/count)
 
 
 def prompt():

control/adder/coroadder0.py

@@ -3,9 +3,13 @@ Closing a generator raises ``GeneratorExit`` at the pending ``yield``
 
     >>> adder = adder_coro()
     >>> next(adder)
+    0
     >>> adder.send(10)
+    10
     >>> adder.send(20)
+    30
     >>> adder.send(30)
+    60
     >>> adder.close()
     -> total: 60  terms: 3  average: 20.0
 
@@ -14,7 +18,9 @@ Other exceptions propagate to the caller:
 
     >>> adder = adder_coro()
     >>> next(adder)
+    0
     >>> adder.send(10)
+    10
     >>> adder.send('spam')
     Traceback (most recent call last):
       ...
@@ -25,13 +31,13 @@ Other exceptions propagate to the caller:
 
 def adder_coro(initial=0):
     total = initial
-    num_terms = 0
+    count = 0
     try:
         while True:
-            term = yield
+            term = yield total
             total += term
-            num_terms += 1
+            count += 1
     except GeneratorExit:
-        average = total / num_terms
+        average = total / count
         msg = '-> total: {}  terms: {}  average: {}'
-        print(msg.format(total, num_terms, average))
+        print(msg.format(total, count, average))