# func.py

import sys
import traceback

# Displays error messages without the full stack trace
def print_exception(tb):
    type, value = tb[:2]
    traceback.print_exception(type, value, None, 0)


# Python function parameters must match arg list

def f(x):
    print x

f(1)

try:
    f()
except TypeError:
    print_exception(sys.exc_info())

print


# Default args

def check_password(password, numRetries=3, 
        prompt='Enter password: '):
    for i in range(numRetries):
        input = raw_input(prompt)
        if input == password:
            return True
    return False

print check_password('xyzzy', 1)
print check_password('xyzzy', prompt='Password: ')

print


# Mutable defaults usually not wanted

def f(a, b=[]):
    b.append(a)
    print b

f(1)
f('abc')

# Better to use None and bind to a new list each time

def f(a, b=None):
    if b is None:
        b = []
    b.append(a)
    print b

f(1)
f('abc')

print


# *args is tuple; **kwargs is dict

def f(*args, **kwargs):
    args = [repr(arg) for arg in args]
    print ', '.join(args)
    for key, value in kwargs.iteritems():
        print "%s: %s" % (key, value)

f(1, 2, 'abc', name='Joe', size=3.5)

print


# Can pass in *args and **kwargs

def g(name, address, phone):
    print name
    print address
    print phone

d = {'name':'Joe', 'address':'NY, NY', 'phone':'555-1212'}
print d
g(**d)