solidPrinciples.txt

1)readable
    if-else ladder is difficult in this case.
2)Testable
    chnaging behaviour of one animal, will chnage behaviour of other animals also, leading to
    breaking of test cases.
3)Extensible
    If we have iported the code from library we cnt modify the code, because we dnt have access 
    to it.for this reason we are unable to ectend the code.
4)Maintainable
    if multiple devs are working, this will lead to merge conflicys.

Robert C. Martin, Uncle Bob


S - Single Responsibility - 
    Every Unit of code should have one simple well-defined responisibility.
    Any unit of code should have excatly 1 reson to change.
    if some peace code is serving multiple responisibilities- break it down into 

    solution - mark the class as abstract.
O - Open Closed
 your code should be closed for modification and for extending.
 instead of using if-else use cases, we can define classes, so that users of library can
    extend my base class and implement new behaviours.

then we have kiwi cannot fly example. solutions -
    1)do not implemente method - code will not compile
    2)throw exception - code breaks without chnaging code
    3)redesign the system
        we defined a new interface and only classes which needs fly method need to implement
        this interface.kiwi does not fly, so it will implement this interface.now
        compiler forces to object to be type interface before calling this method.
    L - Liskov Substitution

        Any functionality that works in parent class must also works for all child classes.
        any extension to existing code should not break the existing code.
    
    
    
    I - Interface Segregation

        code should not br forced to implement a method that it should not need

    D - Dependency Inversion
        
        dnt create dependencies inject them.
        high level module should not depend on low level details
        instead hight level modules should only high level abstraction(interface/ classes)