Lines
of_string s are s's lines, including empty ones. In particular, this is [""] on the empty string.
val fold : ?file:B00_std.Fpath.t -> string -> (int -> string -> 'a -> 'a) -> 'a -> ('a, string) Stdlib.resultParse errors
val err : int -> ('a, Stdlib.Format.formatter, unit, 'b) Stdlib.format4 -> 'aerr n fmt formats an error message for line n as "%d:" ^^
    fmt and raises Failure with no trace.
val err_file : ?file:B00_std.Fpath.t -> string -> ('a, string) Stdlib.resulterr_file ~file e is the error message e for file file formatted as "%a:%s" Fpath.pp_unquoted f s