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��^c @ sN d Z d � Z d � Z d d d � � YZ d � Z e d k rJ e � n d S( s Example of a generator: re-implement the built-in range function
without actually constructing the list of values.
OldStyleRange is coded in the way required to work in a 'for' loop before
iterators were introduced into the language; using __getitem__ and __len__ .
c C s� y� t | � d k r, d t | d � d f St | � d k r_ t | d � t | d � d f St | � d k r� | d d k r� t d � � n t d � | D� � St d t | � � � Wn t k
r� t d � � n Xd S(
sg Take list of arguments and extract/create proper start, stop, and step
values and return in a tuplei i i i s step argument must not be zeroc s s | ] } t | � Vq d S( N( t int( t .0t x( ( s* /usr/lib64/python2.7/Demo/classes/Range.pys <genexpr> s s$ range() accepts 1-3 arguments, givensA range() arguments must be numbers or strings representing numbersN( t lenR t
ValueErrort tuplet TypeError( t arglist( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt
handleargs s !
c g sA t | � \ } } } | } x | | k r< | V| | 7} q Wd S( s, Function to implement 'range' as a generatorN( R ( t at startt stopt stept value( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt genrange s
t oldrangec B s2 e Z d Z d � Z d � Z d � Z d � Z RS( s Class implementing a range object.
To the user the instances feel like immutable sequences
(and you can't concatenate or slice them)
Done using the old way (pre-iterators; __len__ and __getitem__) to have an
object be used by a 'for' loop.
c G sE t | � \ | _ | _ | _ t d | j | j | j � | _ d S( s� Initialize start, stop, and step values along with calculating the
nubmer of values (what __len__ will return) in the rangei N( R R
R R t maxR ( t selfR ( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt __init__, s c C s d | j | j | j f S( s- implement repr(x) which is also used by prints range(%r, %r, %r)( R
R R ( R ( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt __repr__2 s c C s | j S( s implement len(x)( R ( R ( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt __len__6 s c C s> d | k o | j k n r1 | j | j | St d � d S( s implement x[i]i s range[i] index out of rangeN( R R
R t
IndexError( R t i( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt __getitem__: s ( t __name__t
__module__t __doc__R R R R ( ( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyR " s
c
C s9 d d l } d d l } | j d d d � } t t d d d � � } t t d d d � � } | | k su | | k r� t d | | | f � � n d GH| j � } x t d � D] } q� W| j � } x t d � D] } q� W| j � } x | j d � D] } q� W| j � } | | Gd GH| | Gd GH| | Gd
GHd S( Ni����i id i sE error in implementation:
correct = %s
old-style = %s
generator = %ss Timings for range(1000):i� s sec (old-style class)s sec (generator)s sec (built-in)( t timet __builtin__t ranget listR R t Exception(
R R t correct_resultt oldrange_resultt genrange_resultt t1R t t2t t3t t4( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt testB s*
t __main__N( ( R R R R R' R ( ( ( s* /usr/lib64/python2.7/Demo/classes/Range.pyt <module> s