NumTok.Unsigned
val is_nat : t -> bool
val to_nat : t -> string option
val sprint : t -> string
val parse : char Gramlib.Stream.t -> t
Parse a positive Coq number. Precondition: the first char on the stream is already known to be a digit ([0-9]). Precondition: at least two extra chars after the number to parse.
The recognized syntax is:
val parse_string : string -> t option
Parse the string as a non negative Coq number, if possible