Make findNearestUsers() code in soc/logic/site/id_user.py more generic and
move it to soc/logic/model.py. Orginal findNearest...() functions in
id_user.py are now convenience wrappers.
Add typed-query string construction functions to model.py.
Move getFulLClassName() from key_name.py model.py, since it has more to do
with Model types than key names.
Swap 'offset' and 'limit' and make 'limit' arguments non-optional. Also,
stop adding 1 inside the ...ForLimitAndOffset() functions and make the
callers do it (since it was being added for a very UI-specific reason of
whether or not to display a "Next>" link).
Patch by: Todd Larsen
Review by: Pawel Solyga
Review URL: http://codereviews.googleopensourceprograms.com/1401
"""
Common checksum routines (used in multiple localflavor/ cases, for example).
"""
__all__ = ['luhn',]
LUHN_ODD_LOOKUP = (0, 2, 4, 6, 8, 1, 3, 5, 7, 9) # sum_of_digits(index * 2)
def luhn(candidate):
"""
Checks a candidate number for validity according to the Luhn
algorithm (used in validation of, for example, credit cards).
Both numeric and string candidates are accepted.
"""
if not isinstance(candidate, basestring):
candidate = str(candidate)
try:
evens = sum([int(c) for c in candidate[-1::-2]])
odds = sum([LUHN_ODD_LOOKUP[int(c)] for c in candidate[-2::-2]])
return ((evens + odds) % 10 == 0)
except ValueError: # Raised if an int conversion fails
return False