/Prelude-v17.0.0/Bool/fold

Copy path to clipboard

Examples

fold True Natural 0 1 ≡ 0
fold False Natural 0 1 ≡ 1

Source

{-
`fold` is essentially the same as `if`/`then`/else` except as a function
-}
let fold
: ∀(b : Bool) → ∀(bool : Type) → ∀(true : bool) → ∀(false : bool) → bool
= λ(b : Bool) →
λ(bool : Type) →
λ(true : bool) →
λ(false : bool) →
if b then true else false

let example0 = assert : fold True Natural 0 1 ≡ 0

let example1 = assert : fold False Natural 0 1 ≡ 1

in fold