unionWith.js•1.02 kB
var _concat = require('./internal/_concat');
var _curry3 = require('./internal/_curry3');
var uniqWith = require('./uniqWith');
/**
* Combines two lists into a set (i.e. no duplicates) composed of the elements
* of each list. Duplication is determined according to the value returned by
* applying the supplied predicate to two list elements.
*
* @func
* @memberOf R
* @since v0.1.0
* @category Relation
* @sig (a -> a -> Boolean) -> [*] -> [*] -> [*]
* @param {Function} pred A predicate used to test whether two items are equal.
* @param {Array} list1 The first list.
* @param {Array} list2 The second list.
* @return {Array} The first and second lists concatenated, with
* duplicates removed.
* @see R.union
* @example
*
* var l1 = [{a: 1}, {a: 2}];
* var l2 = [{a: 1}, {a: 4}];
* R.unionWith(R.eqBy(R.prop('a')), l1, l2); //=> [{a: 1}, {a: 2}, {a: 4}]
*/
module.exports = _curry3(function unionWith(pred, list1, list2) {
return uniqWith(pred, _concat(list1, list2));
});