Peng Yu wrote:
Suppose I have a list of strings, A. I want to compute the list (call
it B) of strings that are elements of A but doesn't match a regex. I
could use a for loop to do so. In a functional language, there is way
to do so without using the for loop.
In functional language, there is no looping, so that argument is kind of
pointless. The looping construct in many functional language is a syntax
sugar for recursion.
In python, instead of explicit loop, you can use either:
map(pattern.match, list_of_strs)
or
[pattern.match(mystr) for mystr in list_of_strs]
or if you want to be wicked evil, you can write a recursive function as
such:
def multimatcher(list_of_strs, index=0):
return [] if index >= len(list_of_strs) else (
multimatcher(
list_of_strs[index + 1]
).append(
pattern.match(list_of_strs[index])
)
)
--
http://mail.python.org/mailman/listinfo/python-list
