/Prelude-v21.1.0/Natural/sum.dhall

Copy path to clipboard

Add all the numbers in a List

Examples

sum [ 2, 3, 5 ] ≡ 10
sum ([] : List Natural) ≡ 0

Source

--| Add all the numbers in a `List`
let sum
: List Natural → Natural
= λ(xs : List Natural) →
List/fold Natural xs Natural (λ(l : Natural) → λ(r : Natural) → l + r) 0

let example = assert : sum [ 2, 3, 5 ] ≡ 10

let example = assert : sum ([] : List Natural) ≡ 0

in sum