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module Main where | |
import Data.Typelevel.Num (class LtEq, class Mod, class Pos, type (:*), D0, D2, D5, D6, D8, d8) | |
type D256 = D2 :* D5 :* D6 | |
testPositive :: ∀ a . Pos a => a -> Boolean | |
testPositive _ = true | |
testLtEq256 :: ∀ a . LtEq a D256 => a -> Boolean | |
testLtEq256 _ = true | |
testMod8remainder0 :: ∀ a . Mod a D8 D0 => a -> Boolean | |
testMod8remainder0 _ = true | |
proove8isPositive :: Boolean | |
proove8isPositive = testPositive d8 | |
proove8isLtEq256 :: Boolean | |
proove8isLtEq256 = testLtEq256 d8 | |
proove8Mod8remainder0Ok :: Boolean | |
proove8Mod8remainder0Ok = testMod8remainder0 d8 | |
class (Pos m, LtEq m D256, Mod m D8 D0) <= IsPowerOf2 m | |
instance isPowerOf2TypeLevel :: IsPowerOf2 D8 | |
{- | |
Error found: | |
in module Main | |
at src/Main.purs line 29, column 1 - line 29, column 44 | |
No type class instance was found for | |
Data.Typelevel.Num.Sets.Pos t0 | |
The instance head contains unknown type variables. Consider adding a type annotation. | |
while checking that expression #dict LtEq | |
has type {} | |
in value declaration isPowerOf2TypeLevel | |
where t0 is an unknown type | |
See https://github.com/purescript/documentation/blob/master/errors/NoInstanceFound.md for more information, | |
or to contribute content related to this error. | |
-} |
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