I love modern JavaScript libraries.  You get a lot of bang for your buck, keep your code clean, and make my life as a JavaScript developer easier in general.  I regularly use both jQuery and Prototype in my projects.  jQuery is a fantastic javascript library with excellent CSS selector capabilities and DOM manipulation. It’s light-weight and really fast. Prototype is an excellent all-purpose library with many great utility features, including string manipulation, enumerable arrays and hashes. I love using jQuery for its speed and simplicity, but I miss Prototype’s utilities. Luckily, jQuery is very extensible with its versatile plugin system.  dotString is a jQuery plugin that aims to bring Prototype’s string manipulation functions to jQuery.

The dotString home page can be found at http://www.stilldesigning.com/dotstring/.  jQuery ports over all of Prototype’s String functions.  (Except for toArray, which is just an alias of JavaScript’s split function.), and it does it “the jQuery way”.  i.e., without extending JavaScript’s built-in prototypes.  It’s not that I necessarily think that extending prototypes is good or bad; it’s more of a “when in Rome” kind of thing.  Most functions are completely rewritten due to inner dependencies within Prototype, but some are near-direct copies of Sam Stephenson’s (Prototype’s esteemed author) original code, and credited as such.  The library weighs in at 5k compressed, and if you really want to extend the String prototype, it can do that, too.  Documentation can be found on the dotstring home page and more completely in the comments of the uncompressed library.