m ⇒ m String
emptyLine = spacing <* eol

emptyOrCommentLines ∷ Parser m ⇒ m [String]
emptyOrCommentLines = many (try empt
isHex ∷ Parser m ⇒ m Char
isHex = (lookAhead ∘ try) (spacing *> satisfy ((∧) <$> isHexDigit <*> not ∘ isUpper))
isHex = (lookAhead ∘ try) (spacing *> satisfy ((∧) <$> isHexDigit <*> not ∘ isUpper))