token handlers follow for: white space, comment, string, identifier, number, operator
function white() {
    
        var c = walker.ch,
            token = '',
            conf = getConf();
    
        while (c === " " || c === "\t") {
            token += c;
            c = walker.nextChar();
        }
    
        tokener(token, 'white', conf);
    
    }