splitAt package:base-compat

splitAt n xs returns a pair consisting of the prefix of xs of length n and the remaining stream immediately following this prefix.

'splitAt' n xs == ('take' n xs, 'drop' n xs)
xs == ys ++ zs where (ys, zs) = 'splitAt' n xs

splitAt n xs returns a tuple where first element is xs prefix of length n and second element is the remainder of the list:

>>> splitAt 6 "Hello World!"
("Hello ","World!")

>>> splitAt 3 [1,2,3,4,5]
([1,2,3],[4,5])

>>> splitAt 1 [1,2,3]
([1],[2,3])

>>> splitAt 3 [1,2,3]
([1,2,3],[])

>>> splitAt 4 [1,2,3]
([1,2,3],[])

>>> splitAt 0 [1,2,3]
([],[1,2,3])

>>> splitAt (-1) [1,2,3]
([],[1,2,3])

It is equivalent to (take n xs, drop n xs) when n is not _|_ (splitAt _|_ xs = _|_). splitAt is an instance of the more general genericSplitAt, in which n may be of any integral type.