/Prelude-v19.0.0/List/any.dhall

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Returns True if the supplied function returns True for any element in the List

Examples

any Natural Natural/even [ 2, 3, 5 ] ≡ True
any Natural Natural/even ([] : List Natural) ≡ False

Source

{-|
Returns `True` if the supplied function returns `True` for any element in the
`List`
-}
let any
: ∀(a : Type) → (a → Bool) → List a → Bool
= λ(a : Type) →
λ(f : a → Bool) →
λ(xs : List a) →
List/fold a xs Bool (λ(x : a) → λ(r : Bool) → f x || r) False

let example0 = assert : any Natural Natural/even [ 2, 3, 5 ] ≡ True

let example1 = assert : any Natural Natural/even ([] : List Natural) ≡ False

in any