What characters are valid for JavaScript variable names?

Question

Which characters can be used for naming a JavaScript variable?

I want to create a small \"extension library\" for my non-JavaScript users here at work (who all seem

Answer 1

in case regular expressions is not a must, wouldn't it be better to just ask the browser to decide using eval ?

function isValidVarName( name ) {
    try {
        // Update, previoulsy it was
        // eval('(function() { var ' + name + '; })()');
        Function('var ' + name);
    } catch( e ) {
        return false;
    }
    return true;
}

isValidVarName('my_var');     // true
isValidVarName('1');          // false