Eager_and_positions.Lexbuf_consumer
val create : unit -> t
val parse : t -> Lexing.lexbuf -> parsed_value
Consume exactly one s-expression from the given lexing buffer
val parse_opt : t -> Lexing.lexbuf -> parsed_value option
Consume exactly one s-expression from the given lexing buffer. Returns None
if the end of input is reached before seeing any s-expression.