1. A lightweight pattern validation system for a client device receiving markup defining a form, comprising: a processor said processor further comprising: a validation processor separate from said markup and configured with a prototype interface for receiving both a field validation pattern and also form based input to be validated against said field validation pattern; a validation script library within said client device and packaging said validation processor, wherein the form has at least one form based input field programmed for validation using said validation processor: a library reference to said script library disposed in said markup; a function call to said validation processor further disposed in said markup, said function call having a configuration for passing a reference to a value in said at least one form based input field for validation in said validation processor: a plurality of additional function calls to said validation processor disposed in said markup, each additional one of said functional calls having a configuration for passing a reference to a value in a corresponding form based input field for validation in said validation processor: and a validation shell function encapsulating said function calls.