nextToken (
        s,
        start,
        end,
        mode,
        )

nextToken Skip over whitespace and return a token, which is a dictionary with at least three attributes type, start and end. start and end are the indices for the start and end of the token. Depending on the value of type, there may be other attributes: type == key key is the type of key type == abbreviation string is the actual abbreviation string type == qualifier none type == identifier 'string is the actual identifier string type == operator operator is the operator type type == end of input none

lexString (
        s,
        start,
        end,
        type,
        )

lexString Grab a quoted string from the input