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var R = require('../source');var eq = require('./shared/eq');
describe('reduce', function() {  var add = function(a, b) {return a + b;};  var mult = function(a, b) {return a * b;};
  it('folds simple functions over arrays with the supplied accumulator', function() {    eq(R.reduce(add, 0, [1, 2, 3, 4]), 10);    eq(R.reduce(mult, 1, [1, 2, 3, 4]), 24);  });
  it('dispatches to objects that implement `reduce`', function() {    var obj = {x: [1, 2, 3], reduce: function() { return 'override'; }};    eq(R.reduce(add, 0, obj), 'override');    eq(R.reduce(add, 10, obj), 'override');  });
  it('returns the accumulator for an empty array', function() {    eq(R.reduce(add, 0, []), 0);    eq(R.reduce(mult, 1, []), 1);    eq(R.reduce(R.concat, [], []), []);  });
  it('Prefers the use of the iterator of an object over reduce (and handles short-circuits)', function() {    var symIterator = (typeof Symbol !== 'undefined') ? Symbol.iterator : '@@iterator';
    function Reducible(arr) {      this.arr = arr;    }
    Reducible.prototype.reduce = function(f, init) {      var acc = init;      for (var i = 0; i < this.arr.length; i += 1) {        acc = f(acc, this.arr[i]);      }      return acc;    };
    Reducible.prototype[symIterator] = function() {      var a = this.arr;      return {        _pos: 0,
        next: function() {          if (this._pos < a.length) {            var v = a[this._pos];            this._pos += 1;            return {              value: v,              done: false            };          } else {            return {              done: true            };          }        }      };    };
    var xf = R.take(2);    var apendingT = { };    apendingT['@@transducer/result'] = R.identity;    apendingT['@@transducer/step'] = R.flip(R.append);
    var rfn = xf(apendingT);    var list = new Reducible([1, 2, 3, 4, 5, 6]);
    eq(R.reduce(rfn, [], list), [1, 2]);  });
  it('short circuits with reduced', function() {    var addWithMaxOf10 = function(acc, val) {return acc + val > 10 ? R.reduced(acc) : acc + val;};    eq(R.reduce(addWithMaxOf10, 0, [1, 2, 3, 4]), 10);    eq(R.reduce(addWithMaxOf10, 0, [2, 4, 6, 8]), 6);  });});