def r_map_really_tail(fn, arg):
aux = tail_fnc(lambda arg: pattern_match((
(pair(identity, is_none), lambda arr: aux([arr[0], []])),
(
pair(hd_tl_partial(identity, is_blank), identity),
lambda arr: arr[1] + [fn(arr[0][0])]
),
(
pair(hd_tl_partial(identity, identity), identity),
lambda arr: aux([arr[0][1], arr[1] + [fn(arr[0][0])]])
),
), arg))
return aux([arg, None])
from pyfunc.curry import curry_n
from pyfunc.pattern_match import (
pattern_match, hd_tl_partial, is_blank, identity, match_curry,
)
r_map = lambda fn, arg: pattern_match((
(hd_tl_partial(identity, is_blank), lambda arr: [fn(arr[0])]),
(
hd_tl_partial(identity, identity),
lambda arr: [fn(arr[0])] + r_map(fn, arr[1])
),
), arg)
r_map_curry = curry_n(r_map, 2)
twice = r_map_curry(lambda x: x * 2)
is_none = match_curry(lambda obj: obj is None)
pair = lambda match_x, match_y: lambda arr: (match_x(arr[0]), match_y(arr[1]))
def r_map_tail(fn, arg):
aux = lambda arg: pattern_match((
(pair(identity, is_none), lambda arr: aux([arr[0], []])),
(
pair(hd_tl_partial(identity, is_blank), identity),
lambda arr: arr[1] + [fn(arr[0][0])]
),
(
pair(hd_tl_partial(identity, identity), identity),
lambda arr: aux([arr[0][1], arr[1] + [fn(arr[0][0])]])