/Prelude-v23.0.0/List/null.dhall

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Returns True if the List is empty and False otherwise

Examples

null Natural [ 0, 1, 2 ] ≡ False
null Natural ([] : List Natural) ≡ True

Source

--| Returns `True` if the `List` is empty and `False` otherwise
let null
: ∀(a : Type) → List a → Bool
= λ(a : Type) → λ(xs : List a) → Natural/isZero (List/length a xs)

let example0 = assert : null Natural [ 0, 1, 2 ] ≡ False

let example1 = assert : null Natural ([] : List Natural) ≡ True

in null