getValidInput always throwing an exception

[GoogleCodeExporter]

What steps will reproduce the problem?
1. $ESAPI.validator().getValidInput("test", "hello@world.com", "Email", 50, 
true);
2.
3.

What is the expected output? What do you see instead?
Expected : "hello@world.com"
seen : null

What version of the product are you using? On what operating system?
esapi4js-0.1.3

Please provide any additional information below.
a couple of issues I encountered while trying to debug:
checkEmpty function returns null or nothing. as a result the following line in 
getValidInput always returns null.

            if ( checkEmpty( sContext, sInput ) == null ) {
                return null;
            }

if I fix this, I still run into an exception in checkWhitelist. Seems like it 
is throwing an error IF the input matches the expression. 

if(sInput.match(p)) {
...
}

should it be if(!sInput.match(p)){}

?

Original issue reported on code.google.com by subodh.s...@gmail.com on 9 Sep 2013 at 4:38