Job Security (in Python) (Christopher Neugebauer)

Transcript

1. Hello Canadia!
   

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2. Job Security
   (in Python)
   Christopher Neugebauer
   @chrisjrn
   http://chris.neugebauer.id.au
   

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3. Hello!
   

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4. Why do people
   code Python?
   

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5. “Readability”
   -- Raymond Hettinger,
   PyCon US 2013
   

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6. “Readability Counts”
   -- Tim Peters,
   “The Zen of Python”
   (import this)
   

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7. PEP 0008
   “Style Guide for Python Code”
   

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9. Readability Sucks.
   

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10. 1. People can
    comprehend your code.
    

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11. 2. You can maintain
    your own code.
    

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12. 3. Your code will be
    more readily reusable.
    

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13. THIS IS ALL BAD.
    

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14. How do I write
    unmaintainable code?
    

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15. 1) Obvious
    variable names
    

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16. 1) Obvious
    (to you)
    variable names
    

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17. • Callables: Superheroes
    • Classes: Musical characters
    • Strings: Famous actors
    • Numbers: Movie characters
    

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18. MerryPoppins.captain_america(matt_damon, james_bond)
    

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19. Spiderman.spiderman(spiderman)
    

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20. 2) Metaprogramming
    

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21. class Collection(Magic):
    def get_spam(self):
    return self.spam
    def set_spam(self, default):
    self.spam = default
    

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22. >>> c = Collection()
    >>> c.set_spam(“eggs”)
    

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23. >>> c = Collection()
    >>> c.set_spam(“eggs”)
    Traceback (most recent call last):
    File "", line 1, in
    File "", line 10, in
    __getattribute__
    TypeError: instancemethod expected at
    least 2 arguments, got 0
    

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24. Help on Collection in module __main__ object:
    class Collection(Magic)
    | Method resolution order:
    | Collection
    | Magic
    | __builtin__.object
    |
    | Methods defined here:
    |
    | get_spam(self)
    |
    | set_spam(self, default)
    

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25. TRANSLATE = (("get","_bork_"), ("set","_bork_"),
    ("canhas" , "get"), ("ihasa" , "set"))
    class Magic(object):
    def __getattribute__(self, attribute):
    oa = attribute
    for (key,val) in TRANSLATE:
    attribute = attribute.replace(key, val)
    try:
    return object.
    __getattribute__(self,attribute)
    except AttributeError:
    return type(object.
    __getattribute__(self, oa))
    

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26. c.ihasa_spam("foo") -> c.set_spam(“foo”)
    c.canhas_spam() -> c.get_spam()
    

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27. 3) Monkey patching
    

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28. “A batteries-included
    standard library”
    -- Raymond Hettinger,
    PyCon US 2013
    

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29. Roll your own
    standard library
    

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30. >>> import math
    >>> math.cos(0)
    

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31. >>> import math
    >>> math.cos(0)
    0.0
    

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32. >>> import magic
    >>> import math
    >>> math.cos(0)
    0.0
    

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33. import math
    math.cos, math.sin = math.sin, math.cos
    

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34. - End -
    

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35. This talk was a joke.
    

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36. Don’t do this.
    

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37. The end.
    Christopher Neugebauer
    @chrisjrn
    http://chris.neugebauer.id.au
    

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