34 lines
894 B
JavaScript
34 lines
894 B
JavaScript
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"use strict";
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/**
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* RegexParser
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* Parses a string input.
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*
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* @name RegexParser
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* @function
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* @param {String} input The string input that should be parsed as regular
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* expression.
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* @return {RegExp} The parsed regular expression.
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*/
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var RegexParser = module.exports = function (input) {
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// Validate input
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if (typeof input !== "string") {
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throw new Error("Invalid input. Input must be a string");
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}
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// Parse input
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var m = input.match(/(\/?)(.+)\1([a-z]*)/i);
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// If there's no match, throw an error
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if (!m) {
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throw new Error("Invalid regular expression format.");
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}
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// Filter valid flags: 'g', 'i', 'm', 's', 'u', and 'y'
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var validFlags = Array.from(new Set(m[3])).filter(function (flag) {
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return "gimsuy".includes(flag);
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}).join("");
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// Create the regular expression
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return new RegExp(m[2], validFlags);
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};
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