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Commit f988008

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CLASS
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‎Class-Attributes/class-attributes-1.py

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#!/usr/bin/env python2.7
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# class-attributes-1.py
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# Here we define an attribute under the class `YourClass`
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# as well as an attribute within the function.
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# The attribute defined in the class is called `class attributes`
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# and the attribute defined in the function is called `instance attributes`.
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class YourClass(object):
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classy = 10
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def set_val(self):
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self.insty = 100
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dd = YourClass()
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dd.classy # This will fetch the class attribute 10.
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dd.set_val()
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dd.insty # This will fetch the instance attribute 100.
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# Once `dd` is instantiated, we can access both the class and instance
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# attributes, ie.. dd.classy and dd.insty.

‎Class-Attributes/class-attributes-2.py

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#!/usr/bin/env python
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# class-attributes-2.py
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# The code below shows two important points:
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# a) A class attribute can be overridden in an instance, even
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# though it is bad due to breaking Encapsulation.
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# b) There is a lookup path for attributes in Python. The first being
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# the method defined within the class, and then the class above it.
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# We are overriding the 'classy' class attribute in the instance 'dd'.
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# When it's overridden, the python interpreter reads the overridden value.
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# But once the new value is deleted with 'del', the overridden value is no longer
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# present in the instance, and hence the lookup goes a level above and gets it from
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# the class.
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class YourClass(object):
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classy = "class value"
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dd = YourClass()
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print(dd.classy) # < This should return the string "class value"
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dd.classy = "Instance value"
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print(dd.classy) # This should return the string "Instance value"
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# This will delete the value set for 'dd.classy' in the instance.
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del dd.classy
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# Since the overriding attribute was deleted, this will print 'class value'.
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print(dd.classy)
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#!/usr/bin/env python
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# class-instance-attributes-1.py
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# This code shows that an Instance can access it's own
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# attributes as well as Class attributes.
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# We have a class attribute named 'count', and we add 1 to
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# it each time we create an instance. This can help count the
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# number of instances at the time of instantiation.
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class InstanceCounter(object):
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count = 0
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def __init__(self, val):
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self.val = val
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InstanceCounter.count += 1
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def set_val(self, newval):
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self.val = newval
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def get_val(self):
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print(self.val)
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def get_count(self):
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print(InstanceCounter.count)
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a = InstanceCounter(5)
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b = InstanceCounter(10)
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c = InstanceCounter(15)
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for obj in (a, b, c):
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print("value of obj: %s" % obj.get_val())
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print("Count : %s" % obj.get_count())

‎README.md

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```
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class myClass():
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```
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[Class Attributes]()
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