29 lines
689 B
JavaScript
29 lines
689 B
JavaScript
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var baseRandom = require('./_baseRandom');
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/**
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* A specialized version of `_.shuffle` which mutates and sets the size of `array`.
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*
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* @private
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* @param {Array} array The array to shuffle.
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* @param {number} [size=array.length] The size of `array`.
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* @returns {Array} Returns `array`.
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*/
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function shuffleSelf(array, size) {
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var index = -1,
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length = array.length,
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lastIndex = length - 1;
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size = size === undefined ? length : size;
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while (++index < size) {
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var rand = baseRandom(index, lastIndex),
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value = array[rand];
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array[rand] = array[index];
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array[index] = value;
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}
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array.length = size;
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return array;
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}
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module.exports = shuffleSelf;
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