var _curry3 = require('./internal/_curry3');
var always = require('./always');
var over = require('./over');


/**
 * Returns the result of "setting" the portion of the given data structure
 * focused by the given lens to the given value.
 *
 * @func
 * @memberOf R
 * @since v0.16.0
 * @category Object
 * @typedefn Lens s a = Functor f => (a -> f a) -> s -> f s
 * @sig Lens s a -> a -> s -> s
 * @param {Lens} lens
 * @param {*} v
 * @param {*} x
 * @return {*}
 * @see R.prop, R.lensIndex, R.lensProp
 * @example
 *
 *      var xLens = R.lensProp('x');
 *
 *      R.set(xLens, 4, {x: 1, y: 2});  //=> {x: 4, y: 2}
 *      R.set(xLens, 8, {x: 1, y: 2});  //=> {x: 8, y: 2}
 */
module.exports = _curry3(function set(lens, v, x) {
  return over(lens, always(v), x);
});