Sourceval to_int : [> `Read ] t -> int option Sourceval to_float : [> `Read ] t -> float option Sourceval index : [> `Read ] t -> char -> int option Sourceval rindex : [> `Read ] t -> char -> int option Sourceval index_from : [> `Read ] t -> int -> char -> int option Sourceval rindex_from : [> `Read ] t -> int -> char -> int option Sourceval find : [> `Read ] t -> [> `Read ] t -> int option Sourceval find_from : [> `Read ] t -> int -> [> `Read ] t -> int option Sourceval rfind : [> `Read ] t -> [> `Read ] t -> int option Sourceval rfind_from : [> `Read ] t -> int -> [> `Read ] t -> int option Sourceval split : [> `Read ] t -> by:[> `Read ] t -> (_ t * _ t) option Sourceval rsplit : [> `Read ] t -> by:[> `Read ] t -> (_ t * _ t) option