andmap and ormap

Diez B. Roggisch deets at nospam.web.de
Tue Mar 14 07:31:39 EST 2006


> Does python have andmap and ormap:
> 
> andmap((lambda t: boolean(t)),L)
> 
> gives True if boolean(t) is True for all t in L and False otherwise?
> And
> 
> ormap((lambda t: boolean(t)),L)
> 
> gives True if boolean(t) is True for some t in L and False otherwise?
> One can use a list comprehension like
> 
> [x for x in L if not(False in map((lambda t: boolean(t)),L))]
> 
> as an example of selection by andmap, and
> 
> [x for x in L if (True in map((lambda t: boolean(t)),L))]
> 
> as an example of selection by ormap.
> 
> How does one define andmap/ormap so its first argument is a boolean
> procedure or lambda?
> 
> def andmap(b,L):
>   if False in map(b,L): return False
>   else: return True
> 
> def ormap(b,L):
>   if True in map(b,L): return True
>   else: return False


import operator

reduce(operator.and_, [predcidate(o) for o in objects])

predicate can be a lambda, if it has to be.

Diez



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