## /Prelude-v21.1.0/Bool/even.dhall

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Returns `True`

if there are an even number of `False`

elements in the list and
returns `False`

otherwise.

This function is the `Monoid`

for the `==`

operation.

### Examples

even [ False, True, False ] ≡ True

even [ False, True ] ≡ False

even [ False ] ≡ False

even ([] : List Bool) ≡ True

### Source

{-|

Returns `True` if there are an even number of `False` elements in the list and

returns `False` otherwise.

This function is the `Monoid` for the `==` operation.

-}

let even

: List Bool → Bool

= λ(xs : List Bool) →

List/fold Bool xs Bool (λ(x : Bool) → λ(y : Bool) → x == y) True

let example0 = assert : even [ False, True, False ] ≡ True

let example1 = assert : even [ False, True ] ≡ False

let example2 = assert : even [ False ] ≡ False

let example3 = assert : even ([] : List Bool) ≡ True

in even