Python

History Created by Guido von Rossum in 1990 (BDFL) and named after Monty Python's Flying Circus Influences: ABC, Lisp, Perl, Haskell and Java Developed and supported by a large team of volunteers - Python Software Foundation Major implementations: CPython, Jython, Iron Python, PyPy

Created by Guido von Rossum in 1990 (BDFL)

and named after Monty Python's Flying Circus

Influences: ABC, Lisp, Perl, Haskell and Java

Developed and supported by a large team of volunteers - Python Software Foundation

Major implementations: CPython, Jython, Iron Python, PyPy

E.g. Projects with Python Websites: Google, YouTube, Yahoo Groups & Maps, CIA.gov Systems: NASA, LALN, CERN, Rackspace Games: Civilization 4, Quark (Quake Army Knife) Mobile phones: Nokia S60 (Symbian), PythonCE P2P: BitTorrent

Websites: Google, YouTube, Yahoo Groups & Maps, CIA.gov

Systems: NASA, LALN, CERN, Rackspace

Games: Civilization 4, Quark (Quake Army Knife)

Mobile phones: Nokia S60 (Symbian), PythonCE

P2P: BitTorrent

What is Python Very high level scripting-cum-programming language (almost like pseudo-code) Multi-paradigm: OOP, Structured, Functional, Aspect-oriented Multi-platform Dynamic Typing Automatic garbage collector for memory management

Very high level scripting-cum-programming language (almost like pseudo-code)

Multi-paradigm: OOP, Structured, Functional, Aspect-oriented

Multi-platform

Dynamic Typing

Automatic garbage collector for memory management

Philosophy “ there is one -and preferably only one- obvious way to do it” “ The long-term usefulness of a language comes not in its ability to support clever hacks, but from how well and how unobtrusively it supports the day-to-day work of programming. The day-to-day work of programming consists not of writing new programs, but mostly reading and modifying existing ones.” - Eric Raymond, 'Why Python?' 2003

“ there is one -and preferably only one- obvious way to do it”

“ The long-term usefulness of a language comes not in its ability to support clever hacks, but from how well and how unobtrusively it supports the day-to-day work of programming. The day-to-day work of programming consists not of writing new programs, but mostly reading and modifying existing ones.”

- Eric Raymond, 'Why Python?' 2003

Readability Forced indentation No curly brackets / do..end / if...endif No semicolons

Forced indentation

No curly brackets / do..end / if...endif

No semicolons

Syntax Types: str, unicode list, tuple, set dict int, float, complex, bool Conditions: if, elif, else Loops: for...in while

Types:

str, unicode

list, tuple, set

dict

int, float, complex, bool

Conditions:

if, elif, else

Loops:

for...in

while

Why Python? Readability, maintainability Fast development and all just works the first time... Dynamic typing and automatic memory management Paradigm of your choice Extensive library

Readability, maintainability

Fast development and all just works the first time...

Dynamic typing and automatic memory management

Paradigm of your choice

Extensive library

Some problems Scripting-like language and compiled and runtime - hence slower than C/C++ and slightly slower than Java Memory economy hard to achieve (high level data-structures) Multiprocessing and Global interpreter lock

Scripting-like language and compiled and runtime - hence slower than C/C++ and slightly slower than Java

Memory economy hard to achieve (high level data-structures)

Multiprocessing and Global interpreter lock

EXAMPLES

Example: Old Directory Cleanup Script

Example: Simple XML Processing

Example: Simple Spell Checker in 21 Lines