function modifierimport { modifier } from "https://deno.land/x/fun@v2.0.0/optic.ts"; modifier<S, A>(modify: (modifyFn: (a: A) => A) => (s: S) => S): Modifier<S, A>Construct a Modifier<S, A. from a modify function. Type ParametersSAParametersmodify: (modifyFn: (a: A) => A) => (s: S) => SReturnsModifier<S, A>