diff --git a/migen/actorlib/control.py b/migen/actorlib/control.py
index 9819c5dfe..dffcb47da 100644
--- a/migen/actorlib/control.py
+++ b/migen/actorlib/control.py
@@ -17,9 +17,9 @@ class For(Actor):
 		if step: params.append("step")
 		self.d_bv = [BV(bits_for(dimension)) for dimension in maxima]
 		l_sink = [("d{0}".format(n), [(p, bv) for p in params])
-			for n, bv in zip(range(len(self.d_bv)), self.d_bv)]
+			for n, bv in enumerate(self.d_bv)]
 		l_source = [("d{0}".format(n), bv)
-			for n, bv in zip(range(len(self.d_bv)), self.d_bv)]
+			for n, bv in enumerate(self.d_bv)]
 		Actor.__init__(self, SchedulingModel(SchedulingModel.DYNAMIC),
 			("sink", Sink, l_sink),
 			("source", Source, l_source))
diff --git a/migen/corelogic/fsm.py b/migen/corelogic/fsm.py
index a3d3ccb67..d2d184817 100644
--- a/migen/corelogic/fsm.py
+++ b/migen/corelogic/fsm.py
@@ -5,7 +5,7 @@ class FSM:
 		self._state_bv = BV(bits_for(len(states)-1))
 		self._state = Signal(self._state_bv)
 		self._next_state = Signal(self._state_bv)
-		for state, n in zip(states, range(len(states))):
+		for n, state in enumerate(states):
 			setattr(self, state, Constant(n, self._state_bv))
 		self.actions = [[] for i in range(len(states))]
 	
@@ -20,7 +20,7 @@ class FSM:
 	
 	def get_fragment(self):
 		cases = [[Constant(s, self._state_bv)] + a
-			for s, a in zip(range(len(self.actions)), self.actions) if a]
+			for s, a in enumerate(self.actions) if a]
 		comb = [
 			self._next_state.eq(self._state),
 			Case(self._state, *cases)
diff --git a/migen/flow/plumbing.py b/migen/flow/plumbing.py
index e9d2454d9..398b3da9e 100644
--- a/migen/flow/plumbing.py
+++ b/migen/flow/plumbing.py
@@ -19,8 +19,8 @@ class Combinator(Actor):
 	def __init__(self, layout, *subrecords):
 		source = Record(layout)
 		subrecords = [source.subrecord(*subr) for subr in subrecords]
-		eps = [("sink{0}".format(x[0]), Sink, x[1])
-			for x in zip(range(len(subrecords)), subrecords)]
+		eps = [("sink{0}".format(n), Sink, r)
+			for x in enumerate(subrecords)]
 		ep_source = ("source", Source, source)
 		eps.append(ep_source)
 		Actor.__init__(self,
@@ -39,8 +39,8 @@ class Splitter(Actor):
 	def __init__(self, layout, *subrecords):
 		sink = Record(layout)
 		subrecords = [sink.subrecord(*subr) for subr in subrecords]
-		eps = [("source{0}".format(x[0]), Source, x[1])
-			for x in zip(range(len(subrecords)), subrecords)]
+		eps = [("source{0}".format(n), Source, r)
+			for n, r in enumerate(subrecords)]
 		ep_sink = ("sink", Sink, sink)
 		eps.append(ep_sink)
 		Actor.__init__(self,