17 lines
454 B
Text
17 lines
454 B
Text
{-|
|
|
Convert an `Integer` to an `Optional Natural`, with negative numbers becoming `None Natural`.
|
|
-}
|
|
let nonNegative = ./nonNegative.dhall
|
|
|
|
let toNatural
|
|
: Integer → Optional Natural
|
|
= λ(n : Integer) →
|
|
if nonNegative n then Some (Integer/clamp n) else None Natural
|
|
|
|
let example0 = assert : toNatural +7 ≡ Some 7
|
|
|
|
let example2 = assert : toNatural +0 ≡ Some 0
|
|
|
|
let example3 = assert : toNatural -3 ≡ None Natural
|
|
|
|
in toNatural
|