var fails = require('../internals/fails');
var isArray = require('../internals/is-array');
var isObject = require('../internals/is-object');
var toObject = require('../internals/to-object');
var fails = require('../internals/fails');
var isArray = require('../internals/is-array');
var isObject = require('../internals/is-object');
var toObject = require('../internals/to-object');
var createProperty = require('../internals/create-property');
var arraySpeciesCreate = require('../internals/array-species-create');
var arrayMethodHasSpeciesSupport = require('../internals/array-method-has-species-support');
var createProperty = require('../internals/create-property');
var arraySpeciesCreate = require('../internals/array-species-create');
var arrayMethodHasSpeciesSupport = require('../internals/array-method-has-species-support');
var IS_CONCAT_SPREADABLE = wellKnownSymbol('isConcatSpreadable');
var MAX_SAFE_INTEGER = 0x1FFFFFFFFFFFFF;
var MAXIMUM_ALLOWED_INDEX_EXCEEDED = 'Maximum allowed index exceeded';
var IS_CONCAT_SPREADABLE = wellKnownSymbol('isConcatSpreadable');
var MAX_SAFE_INTEGER = 0x1FFFFFFFFFFFFF;
var MAXIMUM_ALLOWED_INDEX_EXCEEDED = 'Maximum allowed index exceeded';
// We can't use this feature detection in V8 since it causes
// deoptimization and serious performance degradation
// We can't use this feature detection in V8 since it causes
// deoptimization and serious performance degradation
for (i = -1, length = arguments.length; i < length; i++) {
E = i === -1 ? O : arguments[i];
if (isConcatSpreadable(E)) {
for (i = -1, length = arguments.length; i < length; i++) {
E = i === -1 ? O : arguments[i];
if (isConcatSpreadable(E)) {
if (n + len > MAX_SAFE_INTEGER) throw TypeError(MAXIMUM_ALLOWED_INDEX_EXCEEDED);
for (k = 0; k < len; k++, n++) if (k in E) createProperty(A, n, E[k]);
} else {
if (n + len > MAX_SAFE_INTEGER) throw TypeError(MAXIMUM_ALLOWED_INDEX_EXCEEDED);
for (k = 0; k < len; k++, n++) if (k in E) createProperty(A, n, E[k]);
} else {