46 lines
1.2 KiB
JavaScript
46 lines
1.2 KiB
JavaScript
// Taken from: https://github.com/paulmillr/es6-shim/
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"use strict";
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var toInteger = require("../../../number/to-integer")
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, toPosInt = require("../../../number/to-pos-integer")
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, validValue = require("../../../object/valid-value")
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, objHasOwnProperty = Object.prototype.hasOwnProperty
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, max = Math.max
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, min = Math.min;
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module.exports = function (target, start/*, end*/) {
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var arr = validValue(this)
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, end = arguments[2]
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, length = toPosInt(arr.length)
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, to
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, from
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, fin
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, count
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, direction;
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target = toInteger(target);
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start = toInteger(start);
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end = end === undefined ? length : toInteger(end);
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to = target < 0 ? max(length + target, 0) : min(target, length);
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from = start < 0 ? max(length + start, 0) : min(start, length);
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fin = end < 0 ? max(length + end, 0) : min(end, length);
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count = min(fin - from, length - to);
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direction = 1;
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if (from < to && to < from + count) {
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direction = -1;
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from += count - 1;
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to += count - 1;
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}
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while (count > 0) {
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if (objHasOwnProperty.call(arr, from)) arr[to] = arr[from];
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else delete arr[from];
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from += direction;
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to += direction;
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count -= 1;
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}
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return arr;
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};
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