JavaScript match against array

Question

I would like to know how to match a string against an array of regular expressions.
I know how to do this looping through the array.
I also know how to do this by ma

Answer 1

If you have the literal strings in an array called strings you want to match, you can combine them into an alternation by doing

new RegExp(strings.map(
    function (x) {  // Escape special characters like '|' and '$'.
      return x.replace(/[^a-zA-Z]/g, "\\$&");
    }).join("|"))

If you don't have only literal strings, you want to combine regular expressions, then you use http://code.google.com/p/google-code-prettify/source/browse/trunk/js-modules/combinePrefixPatterns.js

/**
 * Given a group of {@link RegExp}s, returns a {@code RegExp} that globally
 * matches the union of the sets of strings matched by the input RegExp.
 * Since it matches globally, if the input strings have a start-of-input
 * anchor (/^.../), it is ignored for the purposes of unioning.
 * @param {Array.} regexs non multiline, non-global regexs.
 * @return {RegExp} a global regex.
 */