diffusion/src/node_modules/util/regex.js

Diffusion JavaScript client

/**
 * Create a regex matcher function for a given regex expression, with an 
 * optional context for RegEx construction error messages.
 * <P>
 * The returned function will evaluate the generated regex across the entire
 * region of the given input. This is equivalent to Matcher.matches in Java.
 * 
 * @param {String} s - The regular expression 
 * @param {String} [context=""] - The optional context message 
 * @returns {Function} The tester function
 * @throws Error if the regex couldn't be created
 */
function regex(s, context) {
    context = context || "";
    
    if (s === "") {
        throw new Error("Empty regular expression [" + context + "]");
    }
    try {
        var r = new RegExp(s);
        
        return function(test) {
            // Because JS regex will match any part of the test string, 
            // we have to verify the results to ensure the entire part matches
            var m = r.exec(test);
            return m && m[0] === test;
        };
    } catch (e) {
        throw new Error("Bad regular expression [" + e.message + ", " + context + "]");
    }
}

module.exports = regex;