Structure and Interpretation of Computer Programs metaperl

One-line Tree in Python

Using Python's built-in defaultdict we can easily define a tree data structure:

def tree(): return defaultdict(tree)

That's it!

	class _ExceptionHandlerBase:
	def __init__(self, handler_map):
	self._handler_map = handler_map

	def __call__(self, func):
	def wrapper(args, *kwargs):
	with self:
	func(args, *kwargs)

	return wrapper

	Largest 1000 Cities in America
	2013 popuation data - Biggest US Cities By Population

	rank,city,state,population,2000-2013 growth

	1,New York,New York,8405837,4.8%
	2,Los Angeles,California,3884307,4.8%
	3,Chicago,Illinois,2718782,-6.1%
	4,Houston,Texas,2195914,11.0%
	5,Philadelphia,Pennsylvania,1553165,2.6%