Found Method Map in Base Class Property

When LW Python is searching for a method definition in a list of base classes, it starts with the first base class and stops as soon as it finds the method. This property helps LW Python find the correct method definition from a list of base classes.

if definition of method method_name of class first_base in class_defs = method_map, then definition of method method_name of base classes [ first_base, rest ] in class_defs = method_map

If two base classes happen to have the same method, the class that comes later is not considered. Let's see an example of this property. Consider the following program:

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The "Class Definitions" map is as follows:

[ entry "Animal": [ entry "bases": [ ], [ entry "methods": [ entry "__init__": [ entry "params": [ self, [ ] ], [ entry "line": 2, [ ] ] ], [ entry "move": [ entry "params": [ self, [ ] ], [ entry "line": 5, [ ] ] ], [ ] ] ], [ entry "line": 1, [ ] ] ] ], [ entry "Dog": [ entry "bases": [ "Animal", [ ] ], [ entry "methods": [ entry "jump": [ entry "params": [ self, [ ] ], [ entry "line": 8, [ ] ] ], [ ] ], [ entry "line": 7, [ ] ] ] ], [ ] ] ]

Here is a table view:

Class Name Class Key Value Method Key Value

Animal line 1

bases [ ]

methods __init__ params self

line 2

move params self

line 5

Dog line 7

bases Animal

methods jump params self

line 8

Class Name	Class Key	Value	Method Key	Value
Animal	line	1
bases	[ ]
methods	__init__	params	self
line	2
move	params	self
line	5
Dog	line	7
bases	Animal
methods	jump	params	self
line	8

There are 2 entries, 1 for the "Animal" class and another for the "Dog" class.

For conciseness, let's say that the above map is equal to the variable "class_defs."

Now, we claim that:

definition of method "__init__" of class "Animal" in class_defs = [ entry "params": [ self, [ ] ], [ entry "line": 2, [ ] ] ]

then we can conclude:

definition of method "__init__" of base classes [ "Animal", [ ] ] in class_defs = [ entry "params": [ self, [ ] ], [ entry "line": 2, [ ] ] ]

The conclusion is very similar to the condition, except that there is a list ["Animal", []] instead of just "Animal" in the condition. So when is this property useful? Notice that ["Animal", []] is the base class name list for the "Dog" class. Thus, we can use this property to show that the "Dog" class's "__init__" method is equal to the "Animal" class's "__init__" method.

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