Method modify

packages/effect/src/Optic.ts:501–501

* Returns a function `(s: S) => S` that applies `f` to the focused value. * If the optic cannot focus, the original `s` is returned unchanged. * * **Example** (Incrementing a nested field) * * ```ts import.meta.vitest * import { Optic } from "effect" * * type S = { readonly a

(f: (a: A) => A)

   * ```
   */
  modify(f: (a: A) => A): (s: S) => S

  /**
   * Focuses on a property of the current struct/tuple focus.