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36 lines
952 B
JavaScript
36 lines
952 B
JavaScript
6 years ago
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/** Used as references for various `Number` constants. */
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var MAX_SAFE_INTEGER = 9007199254740991;
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/* Built-in method references for those with the same name as other `lodash` methods. */
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var nativeFloor = Math.floor;
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/**
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* The base implementation of `_.repeat` which doesn't coerce arguments.
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*
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* @private
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* @param {string} string The string to repeat.
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* @param {number} n The number of times to repeat the string.
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* @returns {string} Returns the repeated string.
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*/
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function baseRepeat(string, n) {
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var result = '';
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if (!string || n < 1 || n > MAX_SAFE_INTEGER) {
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return result;
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}
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// Leverage the exponentiation by squaring algorithm for a faster repeat.
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// See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details.
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do {
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if (n % 2) {
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result += string;
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}
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n = nativeFloor(n / 2);
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if (n) {
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string += string;
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}
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} while (n);
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return result;
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}
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module.exports = baseRepeat;
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