Method Definition Property

When LW Python reads a new method definition statement, it updates the "Class Definitions" map with the method name, the method parameters, and the current line number. More formally,

Let's break down the conclusion. The method definision is inside the "methods" map, which is inside a "class definition" map, which is finally inside the "Class Definitions" map. Then, to update a method definition, LW Python updates all 3 maps. For example,

if the following are true:

• the line at time 1 = 2
• the tab at time 1 = 1
• statement at line 2, tab 1 = def __init__(self, first_name, last_name, age):
• value at "Person" in map (Class Map at time 1) = [ entry "bases": [ ], [ entry "methods": [ ], [ entry "line": 1, [ ] ] ] ]
• value at "methods" in map [ entry "bases": [ ], [ entry "methods": [ ], [ entry "line": 1, [ ] ] ] ] = [ ]

then Class Map at time (1 + 1) = result of storing (result of storing (result of storing [ entry "params": [ self, [ first_name, [ last_name, [ age, [ ] ] ] ] ], [ entry "line": 2, [ ] ] ] at key: "__init__" in map: [ ]) at key: "methods" in map: [ entry "bases": [ ], [ entry "methods": [ ], [ entry "line": 1, [ ] ] ] ]) at key: "Person" in map: (Class Map at time 1)

That is pretty hard to read, so let's try a table view.

Before the method data is added, the "Person" class definition is:

Key	Value
line	1
bases	[ ]
methods	[ ]

The "methods" map is empty. Now, a new method "__init__" was found. The new method definition is the following map:

Key	Value
params	[self, [first_name, [last_name, [age, []]]]]
line	2

LW Python creates a new entry in the "methods" map where the key is "__init__" and the value is the above definition. Then the "methods" entry in the "Person" class definition map is updated with the new "methods" map.

Thus the new "Person" class definition is:

Key	Value
line	1
bases	[ ]
methods	__init__ : "__init__" method definition

Finally, the "Person" entry in the "Class Definitions" map is updated with the new class definition map above. In words, the conclusion is:

Class Map at time 2 = [ entry "Person": [ entry "bases": [ ], [ entry "methods": [ entry "__init__": [ entry "params": [ self, [ first_name, [ last_name, [ age, [ ] ] ] ] ], [ entry "line": 2, [ ] ] ], [ ] ], [ entry "line": 1, [ ] ] ] ], [ ] ]

Try stepping through the simulator to see LW Python save the method definition.

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