first

node_modules/core-js/internals/array-reduce.js

@@ -0,0 +1,43 @@
+'use strict';
+var aCallable = require('../internals/a-callable');
+var toObject = require('../internals/to-object');
+var IndexedObject = require('../internals/indexed-object');
+var lengthOfArrayLike = require('../internals/length-of-array-like');
+
+var $TypeError = TypeError;
+
+// `Array.prototype.{ reduce, reduceRight }` methods implementation
+var createMethod = function (IS_RIGHT) {
+  return function (that, callbackfn, argumentsLength, memo) {
+    aCallable(callbackfn);
+    var O = toObject(that);
+    var self = IndexedObject(O);
+    var length = lengthOfArrayLike(O);
+    var index = IS_RIGHT ? length - 1 : 0;
+    var i = IS_RIGHT ? -1 : 1;
+    if (argumentsLength < 2) while (true) {
+      if (index in self) {
+        memo = self[index];
+        index += i;
+        break;
+      }
+      index += i;
+      if (IS_RIGHT ? index < 0 : length <= index) {
+        throw $TypeError('Reduce of empty array with no initial value');
+      }
+    }
+    for (;IS_RIGHT ? index >= 0 : length > index; index += i) if (index in self) {
+      memo = callbackfn(memo, self[index], index, O);
+    }
+    return memo;
+  };
+};
+
+module.exports = {
+  // `Array.prototype.reduce` method
+  // https://tc39.es/ecma262/#sec-array.prototype.reduce
+  left: createMethod(false),
+  // `Array.prototype.reduceRight` method
+  // https://tc39.es/ecma262/#sec-array.prototype.reduceright
+  right: createMethod(true)
+};