higher-order-logical-operators/lib/xor/index.js

Allows combination of lower order functions that evaluate to booleans. Extends Array prototype with 'one' function, which takes a callback and returns true if the callback returns true for one and only one member of the array.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
Array.prototype.one = function (callback) {
  return this.reduce(function (p, v, i, a) {
    return p + (callback(v, i, a) ? 1 : 0);
  }, 0) === 1;
};

var xor = exports.xor = function xor() {
  for (var _len = arguments.length, fns = Array(_len), _key = 0; _key < _len; _key++) {
    fns[_key] = arguments[_key];
  }

  return function () {
    for (var _len2 = arguments.length, args = Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
      args[_key2] = arguments[_key2];
    }

    return fns.one(function (fn) {
      return fn.apply(undefined, args);
    });
  };
};