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--- python:about_python:python_inheritance_fundamentals [2018/02/24 23:02] – [What you'll learn] mithat
+++ python:about_python:python_inheritance_fundamentals [2018/02/24 23:38] (current) – [What you'll need to know] mithat
@@ Line 5: / Line 5: @@
 ===== What you'll need to know =====
-  * How to create a basic class definition.
+  * How to create and use a Python class.
   * How to use the ''@property'' decorator.
+  * How to use parameterized constructors.
 ===== What you'll learn =====
-  * Inheritance key concept
+  * Inheritance core concept
   * Generalization and specialization
   * Class heirarchies
   * Inheritance and code reuse
   * Inheritance in Python
-  * Constructors and inheritance
 ===== Inheritance =====
@@ Line 46: / Line 46: @@
 Since you do not need to rewrite the code that is common to both base and derived classes, you end up writing less code. But even more important, when you fix a bug in the base class, it automatically propagates to the derived classes.
-==== Inheritance and polymorphism ====
-Another advantage of using inheritance is that with statically typed languages (such as C++ and Java), it facilitates **polymorphism** (discussed below). Dynamically typed languages (like Python) behave polymorphically almost by definition.
 ===== Inheritance in Python =====
@@ Line 110: / Line 107: @@
 </code>
-===== Parameterized constructor example =====
-Let's now add a ''click_limit'' feature to our ''ClickerCounter''.  When the user clicks past the ''click_limit'', the count will automatically reset to zero. By default, the ''click_limit'' will be 100,000. Let us also let the user set the ''click_limit'' when she or he instantiates a ''ClickerCounter''.
-To do this, we will need to add an instance variable to store the ''click_limit'', add some logic to the ''click'' method, and add a parameterized constructor:
+===== What you should do next =====
-<code python>
+This covers the very basics of inheritance in Python. To level up your use of inheritance in Python, you should next have a look at the following:
-class ClickerCounter():
-    # parameterized constructor
-    def __init__(self, click_limit = 100000):
-        self.count = 0
-        self.click_limit = click_limit
-    # accessor for count
-    def get_count(self):
-        return self.count
-    # click the counter
-    def click(self):
-        if self.count < self.click_limit:
-            self.count = self.count + 1
-        else:
-            self.reset()
-    # reset the count
-    def reset(self):
-        self.count = 0
-</code>
-To use it:
+  * Overriding methods.
+  * Derived class constructors (including calling parent class constructors).
-<code python>
-a = ClickerCounter(3)       # make a clicker-counter that counts up to 3
-a.click()
-a.click()
-a.click()
-print a.get_count()         # should be 3
-a.click()                   # should go from 3 to 0
-print a.get_count()         # should be 0
-</code>
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