006 Python Cookbook 01-01 Unpacking a Sequence

#!/usr/bin/env python


# http://chimera.labs.oreilly.com/books/1230000000393/ch01.html#iterableunpack

# Unpacking a Sequence into Separate Variables

import sys p = (4, 5) print "p is ", p x, y = p print "after x, y = p" print "x is ", x print "y is ", y print "-----------" data = ['ACM', 50, 91.1, (2014, 2, 19)] print "data = ", data name, shares, price, date = data print "after name, shares, price, date = data" print "name = ", name print "shares = ", shares print "price = ", price print "date = ", date print "-----------" name, shares, price, (year, month, day) = data print "after name, shares, price, (year, month, day) = data" print "year = ", year print "month = ", month print "day = ", day print "-----------" p = (4, 5) print "p =", p print "if x, y, z = p" try:     x, y, z = p except ValueError:     print "except ValueError"     i = 0     for msg in sys.exc_info():         print "sys.exc_info()[", i, "]" ,msg;         i+=1 print "-----------" s = "hello" print "s = ", s a1, a2, a3, a4, a5 = s print "after a1, a2, a3, a4, a5 = s" print "a1 = ", a1 print "a2 = ", a2 print "a3 = ", a3 print "a4 = ", a4 print "a5 = ", a5 print "-----------" data = ['dont care', 50, 91.1, ('let', 'it', 'go')] print "data = ", data _, shares, price, _ = data # treat "-" as throw away variable print "after _, shares, price, _ = data" print "shares = ", shares print "price = ", price

p is  (4, 5) after x, y = p x is  4 y is  5 ----------- data =  ['ACM', 50, 91.1, (2014, 2, 19)] after name, shares, price, date = data name =  ACM shares =  50 price =  91.1 date =  (2014, 2, 19) ----------- after name, shares, price, (year, month, day) = data year =  2014 month =  2 day =  19 ----------- p = (4, 5) if x, y, z = p except ValueError sys.exc_info()[ 0 ] <type 'exceptions.ValueError'> sys.exc_info()[ 1 ] need more than 2 values to unpack sys.exc_info()[ 2 ] <traceback object at 0x000000000256ED88> ----------- s =  hello after a1, a2, a3, a4, a5 = s a1 =  h a2 =  e a3 =  l a4 =  l a5 =  o ----------- data =  ['dont care', 50, 91.1, ('let', 'it', 'go')] after _, shares, price, _ = data shares =  50 price =  91.1