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// 22.1.3.3 Array.prototype.copyWithin(target, start, end = this.length)
'use strict';
var toObject = require('./_to-object');
var toAbsoluteIndex = require('./_to-absolute-index');
var toLength = require('./_to-length');
module.exports = [].copyWithin || function copyWithin(target /* = 0 */, start /* = 0, end = @length */) {
var O = toObject(this);
var len = toLength(O.length);
var to = toAbsoluteIndex(target, len);
var from = toAbsoluteIndex(start, len);
var end = arguments.length > 2 ? arguments[2] : undefined;
var count = Math.min((end === undefined ? len : toAbsoluteIndex(end, len)) - from, len - to);
var inc = 1;
if (from < to && to < from + count) {
inc = -1;
from += count - 1;
to += count - 1;
}
while (count-- > 0) {
if (from in O) O[to] = O[from];
else delete O[to];
to += inc;
from += inc;
} return O;
};
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