vue hello world项目
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'use strict';
var toObject = require('../internals/to-object');
var toAbsoluteIndex = require('../internals/to-absolute-index');
var lengthOfArrayLike = require('../internals/length-of-array-like');
var min = Math.min;
// `Array.prototype.copyWithin` method implementation
// https://tc39.es/ecma262/#sec-array.prototype.copywithin
// eslint-disable-next-line es/no-array-prototype-copywithin -- safe
module.exports = [].copyWithin || function copyWithin(target /* = 0 */, start /* = 0, end = @length */) {
var O = toObject(this);
var len = lengthOfArrayLike(O);
var to = toAbsoluteIndex(target, len);
var from = toAbsoluteIndex(start, len);
var end = arguments.length > 2 ? arguments[2] : undefined;
var count = 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;
};