method i128.checked_sub

Checked subtraction: the difference, or none on overflow.

Example:

fn main() io {
  let max: i128 = 170141183460469231731687303715884105727
  let min: i128 = -170141183460469231731687303715884105728
  print("{min.checked_sub(1)}")
  print("{(min + 1).checked_sub(1)}")
}

none
-170141183460469231731687303715884105728

pub(api) fn checked_sub(o: i128) -> i128?

Complexity. O(1).

Since. 1.0.0-beta

Parameters

Returns

i128?

Effects

none declared (pure unless the body says otherwise)

Defined in: std/core/numbers.oxl:1756