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Python: switch statement (a replacement of..)

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  1. ## There is currently no switch statement in Python. Often this is not a problem and can be handled through a series of if-elif-else statements. However, there are many other ways to handle the deficiency. The following example shows how to create a simple switch statement in Python:
  2.  
  3. >>>def a(s):
  4. >>>    print s
  5. >>>def switch(ch):
  6. >>>    try:
  7. >>>      {'1': lambda : a("one"),
  8. >>>       '2': lambda : a("two"),
  9. >>>       '3': lambda : a("three"),
  10. >>>       'a': lambda : a("Letter a")
  11. >>>      }[ch]()
  12. >>>    except KeyError:
  13. >>>      a("Key not Found")
  14. >>>switch('1')
  15. one
  16. >>>switch('a')
  17. Letter a
  18. >>>switch('b')
  19. Key not Found
  20.  
  21.  
  22. ## Remember that we are making use of the following method for checking the existence of a Key...:
  23.  
  24. >>> {1: 2}[1]
  25. >>> 2
  26. >>> {1: 2}[0]
  27. Key Error......
  28.  
  29.  
  30. ## p.s. check also the entry about the use of lambda in a dictionary...

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