1
Fork 0
solar-conflux/purescript/lunarline/idea

73 lines
980 B
Plaintext
Raw Normal View History

2023-10-29 02:10:10 +02:00
map f = case _ of
Nil -> Nil
x:xs -> f x : map f xs
map2 f g xs = map g (map f xs)
----------
map2 f g xs = map g case xs of
Nil -> Nil
x:xs -> f x : map f xs
----------
map2 g f xs = case (case ...) ...
----------
map2 f g xs = case xs of
Nil -> case Nil of
Nil -> Nil
x:xs -> f x : map f xs
x:xs -> case f x : map f xs of
Nil -> Nil
x:xs -> g x : map g xs
----------
map2 f g xs = case xs of
Nil -> Nil
x:xs -> let
a = f x
b = map f xs
in g a : map g b
----------
map2 f g xs = case xs of
Nil -> Nil
x:xs -> g (f x) : map g (map f xs)
----------
map2 f g = case _ of
x:xs -> g (f x) : map2 f g xs
Nil -> Nil
----------
map2 f g = case _ of
x:xs -> (compose g f) x : map2 f g xs
Nil -> Nil
==========
Unify
map2 f g a
with
map u1 u2
u2 = a
==========
Unify
(compose g f) x
with
u1 x
u1 = compose g f
==========
Unify
map2 f g xs
with
map (compose g f) xs
TRUE
map2 = map (compose g f) xs