simplified range_iterator (renamed for consistency)

Author: Brad Walker

src/future/types/newrange.py

@@ -19,6 +19,7 @@
 """
 
 from collections import Sequence, Iterator
+from itertools import islice
 
 
 class newrange(Sequence):
@@ -136,35 +137,27 @@ def __getitem_slice(self, slce):
     def __iter__(self):
         """Return an iterator which enumerates the elements of the
         sequence this range represents."""
-        return rangeiterator(self)
+        return range_iterator(self)
 
 
-class rangeiterator(Iterator):
+class range_iterator(Iterator):
     """An iterator for a :class:`range`.
     """
-
-    def __init__(self, rangeobj):
-        self._range = rangeobj
-
-        # Intialize the "last outputted value" to the value
-        # just before the first value; this simplifies next()
-        self._last = self._range._start - self._range._step
-        self._count = 0
+    def __init__(self, range_):
+        self._stepper = islice(_count(range_.start, range_.step), len(range_))
 
     def __iter__(self):
-        """An iterator is already an iterator, so return ``self``.
-        """
         return self
 
     def next(self):
-        """Return the next element in the sequence represented
-        by the range we are iterating, or raise StopIteration
-        if we have passed the end of the sequence."""
-        self._last += self._range._step
-        self._count += 1
-        if self._count > self._range._len:
-            raise StopIteration()
-        return self._last
+        return next(self._stepper)
+
+
+# itertools.count in Py 2.6 doesn't accept a step parameter
+def _count(start=0, step=1):
+    while True:
+        yield start
+        start += step
 
 
 __all__ = ['newrange']