The purpose of the jWellFormed.js project is to unify client-side form-validation and submission control across a website.

The project seeks to alleviate those who can sympathize with the following realities of web development:

• Client-side form validation is more often than not too bland and dry to avoid the copy-paste train
• Managing if statements becomes increasing complex as more elements are added to a form, especially when ANDing, ORing, and nesting come into play.
• Code-reuse is difficult to achieve with form-validation, because often times client-side code is tightly coupled to particular DOM snippets, and it's often easier to simply rewrite code instead of trying to make it DOM-agnostic.

jWellFormed.js hopes to provide end-users with something slightly better than what's out there now. In comparison with the JQuery Validation plugin, jWellFormed.js seeks to offer something that's a little more interesting to work with and that focuses more on the need for user-defined, one-off type of functionality rather than the boiler-plate CC #, date, email, etc. stuff that most browsers give you for free nowadays via HTML5 input types.

• Embraces jQuery's implict iteration via css-style selectors. Multiple form elements can be validated against the same user-defined Fn's, where the first element in a set to fail validation can be highlighted.
• Experimental support for Async validation via HTTP GET and POST.
• No documentation required, it's super simple! Just see the example page.

Quite simply really. Your function will receive the form element(s) you pass in the .ensure() method. Based off of the element received--and possibly other indicators--you simply return true if it passes your spec or false otherwise.

Example Page for live demo

Maybe come up with a better example page and I may be wrong on the claim that no documention is required.