37 lines
1.0 KiB
JavaScript
37 lines
1.0 KiB
JavaScript
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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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, isPlainArray = require("../../is-plain-array")
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, isArray = Array.isArray
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, slice = Array.prototype.slice
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, objHasOwnProperty = Object.prototype.hasOwnProperty
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, max = Math.max;
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module.exports = function (start, end) {
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var length, result, i;
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if (!this || !isArray(this) || isPlainArray(this)) {
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return slice.apply(this, arguments);
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}
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length = toPosInt(this.length);
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start = toInteger(start);
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if (start < 0) start = max(length + start, 0);
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else if (start > length) start = length;
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if (end === undefined) {
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end = length;
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} else {
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end = toInteger(end);
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if (end < 0) end = max(length + end, 0);
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else if (end > length) end = length;
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}
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if (start > end) start = end;
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result = new this.constructor(end - start);
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i = 0;
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while (start !== end) {
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if (objHasOwnProperty.call(this, start)) result[i] = this[start];
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++i;
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++start;
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}
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return result;
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};
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