isVarInitChar, isVarRestChar :: Char -> Bool
isVarInitChar c = not (isDigit c) && isVarRestChar c && not (elem c [quote, bottom])
isVarInitChar, isVarRestChar :: Char -> Bool
isVarInitChar c = not (isDigit c) && isVarRestChar c && not (elem c [quote, bottom])
isVarInitChar c = not (isDigit c) && isVarRestChar c && not (elem c [quote, bottom])