Commit ffd6bfae authored by Raymond Hettinger's avatar Raymond Hettinger

Explain the advantages of reversed.

parent 03f18e58
......@@ -34,7 +34,7 @@ and returns an iterator that returns the elements of the sequence
in reverse order.
\begin{verbatim}
>>> for i in reversed([1,2,3]):
>>> for i in reversed(xrange(1,4)):
... print i
...
3
......@@ -42,9 +42,12 @@ in reverse order.
1
\end{verbatim}
Compared to extended slicing, \code{range(1,4)[::-1]}, \function{reversed()}
is easier to read, runs faster, and uses substantially less memory.
Note that \function{reversed()} only accepts sequences, not arbitrary
iterators. If you want to reverse an iterator, convert it to
a list or tuple with \function{list()} or \function{tuple()}.
iterators. If you want to reverse an iterator, first convert it to
a list with \function{list()}.
\begin{verbatim}
>>> input = open('/etc/passwd', 'r')
......
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