/**
 * Minimal implementation of lodash's _.set
 * https://lodash.com/docs/4.17.15#set
 *
 * Mutates `obj` in place, creating missing objects/arrays along the path:
 *
 *   const obj = { a: { b: 1 } };
 *   set(obj, 'a.c', 2);      // obj is { a: { b: 1, c: 2 } }
 *   set(obj, 'list.0', 'x'); // obj.list is ['x']
 *
 * See ./set.test.ts for more usage examples
 */
export declare const set: (obj: any, _path: string | string[], value: any) => any;
/**
 * Like `set`, but every object or array along `path` that is not in `copied`
 * is shallow-copied before being written to, so objects shared with the
 * original are never mutated. `obj` itself must already be a copy.
 *
 *   const block = { options: { text: 'a' }, style: { color: 'red' } };
 *   const copy = { ...block };
 *   setCopyOnWrite(copy, 'options.text', 'b', new WeakSet());
 *   // copy.options is a new object: { text: 'b' }
 *   // block.options.text is still 'a'
 *   // copy.style === block.style (untouched branches stay shared)
 */
export declare const setCopyOnWrite: (obj: any, _path: string, value: any, copied: WeakSet<object>) => any;
/**
 * Deletes the property at `path`, the inverse of `set` for an array path.
 * Mutates `obj` in place and does nothing when a parent is missing:
 *
 *   const obj = { a: { b: 1, c: 2 } };
 *   unset(obj, ['a', 'b']); // obj is { a: { c: 2 } }
 *   unset(obj, ['x', 'y']); // no-op
 */
export declare const unset: (obj: any, path: string[]) => any;