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by Chandrashekar Babu
http://www.chandrashekar.info/<[email protected]>>
Why ?1. Most of us have learnt
OOP paradigms using
Java/C++/C#
Due to academic syllabus in most colleges and universities
Why ?2. Most of us have thought that
the best way to write a OO program is to start with creating
a Class!
And hope that JAVA/.NET vm’s figure out how to run our program
Ouch!
Shouldn’t this suffice ?
#PythonZen_9: Although practicality beats purity.
Pythonisms!
Pythonisms #1.Everything is an Object!
This includes classes, modules, functions, types
“If I can touch it - I can surely destroy it!”
Functions are first class objects!
Classes are first class objects!
Modules are first class objects too!
Pythonisms #2.All identifiers are
references to Objects!
This includes variables, object’s attributes,
indices of a sequence, keys of a mapping
Pythonisms #3.All assignments are
assigned-by-references!
All objects are passed-by-references!
“Why copy when you can just refer ?”
Pythonisms #4.All definitions
happen in runtime!
Thus var = Noneis simply unnecessary!
“What’s the point in holding a label when don’t know where you’d stick them to ?”
Pythonisms #5.Variables on their own are
typeless!
Instead, they act as labels to Objects - thus deriving Object’s type.
Note: Objects however are strongly typed!
Pythonisms #6.There is no
“type-casting”!
Instead you do “type conversion”
or “type construction”
“A number is a number! A string is a string!”
Pythonisms #7.Duck-Typing
over Type-checking!
“When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck.”
- James Whitcomb Riley
- Alex Martelli
Pythonisms #8.
Introspection over
Inheritance!
“Ask what the object can do - not where they come from!”
- Me :-)
Pythonisms #9.Generalized functions
over interface methods!
“Sure - I can throw a camera, a pen or a brick - though these objects might have no idea about what to do if thrown around!”
- Me :-)
Pythonisms #10.Succinct-ness
over verbosity!
int(“10”) over
Integer.parseInt(“10”)
Questions ?
‣ Contact: Name: Chandrashekar Babu. Website: http://www.chandrashekar.info/ Email: [email protected] LinkedIn: http://in.linkedin.com/in/chandrashekarbabu/
