Sign Morph
Sign
Morph
char : Morph Sign Char
Sign '+' or '-'
'+'
'-'
bit : MorphOrError Sign Bit error_
Bit.O Positive, Bit.I ⇄ Negative
Bit.O
Positive
Bit.I
Negative
maybeMinusChar : MorphRow Sign Char
An optional '-' sign → Negative, else Positive without consuming Chars.
Char