static (class) methods via decorators

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Objects - Intermediate example from a Well House Consultants training course
More on Objects - Intermediate [link]

This example is described in the following article(s):
• Methods that run on classes (static methods) in Python - [link]

This example references the following resources:
http://www.wellho.net/mouth/2693_.html

Source code: ting2 Module: Y112

""" This example shows how you can write dynamic (or object)
methods in Python - example is "getval", or static methods
using the @staticmethod decorator. You can also write methods
which work in both ways, using the @classmethod decorator.

One of the common requirements in any Object based system is
to write comparators, and this example includes both "larger"
and "largest" methods to illustrat how it's well done in Python.

If you've found this page on our web site, the link above will
take you to further text about staticmethod and classmethod; if
you need to see the URL, it's
        http://www.wellho.net/mouth/2693_.html

"""

class thing(object):
   count = 0

   def __init__(self, value):
      self.value = value
      if value > 6:
         thing.count += 1

   def getval(self):
      return self.value

   # Make it callable on class
   @staticmethod
   def counter():
      return thing.count

   # Make it callable on objects or class
   @classmethod
   def counter2(self):
      # "self" is the object or the class
      return thing.count

   def larger(this,that):
      if this.getval() > that.getval():
          return this
      return that

   @staticmethod
   def largest(these):
      so_far = these[0]
      for tryme in these[1:]:
          so_far = tryme.larger(so_far)
      return so_far

stuff = [thing(4), thing(6), thing(12), thing(9)]

print thing.counter()
print thing.counter2()

lgr = stuff[3].larger(stuff[1])
print lgr.getval()

lgs = thing.largest(stuff)
print lgs.getval()

""" Sample output:

Dorothy-2:pyx grahamellis$ python ting2
2
2
9
12
Dorothy-2:pyx grahamellis$

"""

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in Python
* Python Programming
* Intermediate Python
Also available on on site courses for larger groups

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Other Examples

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