Every absurdity has a champion to defend it.
Oliver Goldsmith
@arpinum/defender is a collection of assertions to do some runtime type checking.
npm install @arpinum/defender --save
Assertion throwing exception when not satisfied:
import { assert } from "@arpinum/defender";
assert("hello").toBeANumber(); // throws: value must be a number
Simple validation returning a boolean:
import { is } from "@arpinum/defender";
is("hello").aNumber(); // false
More examples in examples.