python中迭代器（iterator）用法实例分析

#---------------------------------------#      Name: iterators.py#     Author: Kevin Harris# Last Modified: 03/11/04# Description: This Python script demonstrates how to use iterators.#---------------------------------------myTuple = (1, 2, 3, 4)myIterator = iter( myTuple )print( next( myIterator ) )print( next( myIterator ) )print( next( myIterator ) )print( next( myIterator ) )# Becareful, one more call to next() # and this script will throw an exception!#print myIterator.next() print( " " )#---------------------------------------# If you have no idea how many items # can be safely accesd via the iterator,# use a try/except block to keep your script from crashing.myTuple2 = ( "one", "two", "three", "four" )myIterator2 = iter( myTuple2 )while 1:  try:    print( next( myIterator2 ) )  except StopIteration:    print( "Exception caught! Iterator must be empty!" )    breakinput( '/n/nPress Enter to exit...' )