Name: Anonymous 2017-11-24 17:14
benis f = (f ['d'], f [1])lac.hs:23:22: error:
• No instance for (Num Char) arising from the literal ‘1’
• In the expression: 1
In the first argument of ‘f’, namely ‘[1]’
In the expression: f [1]
Failed, modules loaded: none.
and car cdr = car cdr car
or car cdr = car car cdrlac.hs:14:23: error:
• Occurs check: cannot construct the infinite type:
t ~ t2 -> t -> t1
• In the second argument of ‘car’, namely ‘car’
In the expression: car cdr car
In an equation for ‘Main.and’: Main.and car cdr = car cdr car
• Relevant bindings include
cdr :: t2 (bound at lac.hs:14:9)
car :: t2 -> t -> t1 (bound at lac.hs:14:5)
Main.and :: (t2 -> t -> t1) -> t2 -> t1 (bound at lac.hs:14:1)
lac.hs:17:18: error:
• Occurs check: cannot construct the infinite type:
t ~ t -> t2 -> t1
• In the first argument of ‘car’, namely ‘car’
In the expression: car car cdr
In an equation for ‘Main.or’: Main.or car cdr = car car cdr
• Relevant bindings include
cdr :: t2 (bound at lac.hs:17:8)
car :: t -> t2 -> t1 (bound at lac.hs:17:4)
Main.or :: (t -> t2 -> t1) -> t2 -> t1 (bound at lac.hs:17:1)
In order to make the above work you need to type it explicitly, like
LANGUAGE Rank2Types #-} --for some reason the shitty syntax highlighter bullshit in this site eats the {-#
type CBool = forall a. a -> a -> a
and :: CBool -> CBool -> CBool
or :: CBool -> CBool -> CBool
benis :: (forall a. a -> b) -> (b, b)You can't even do
benis :: (a -> b) -> (b, b) nor benis :: ([a] -> b) -> (b, b) nor anything that does not use a compiler extension. What a great language!