Reason · Reason lets you write simple, fast and quality type safe code while leveraging both the JavaScript & OCaml ecosystems.

sig
 type position = {
  pos_fname : string;
  pos_lnum : int;
  pos_bol : int;
  pos_cnum : int;
 }
 val dummy_pos : Lexing.position
 type lexbuf = {
  refill_buff : Lexing.lexbuf -> unit;
  mutable lex_buffer : bytes;
  mutable lex_buffer_len : int;
  mutable lex_abs_pos : int;
  mutable lex_start_pos : int;
  mutable lex_curr_pos : int;
  mutable lex_last_pos : int;
  mutable lex_last_action : int;
  mutable lex_eof_reached : bool;
  mutable lex_mem : int array;
  mutable lex_start_p : Lexing.position;
  mutable lex_curr_p : Lexing.position;
 }
 val from_channel :
  ?with_positions:bool -> Stdlib.in_channel -> Lexing.lexbuf
 val from_string : ?with_positions:bool -> string -> Lexing.lexbuf
 val from_function :
  ?with_positions:bool -> (bytes -> int -> int) -> Lexing.lexbuf
 val set_position : Lexing.lexbuf -> Lexing.position -> unit
 val set_filename : Lexing.lexbuf -> string -> unit
 val with_positions : Lexing.lexbuf -> bool
 val lexeme : Lexing.lexbuf -> string
 val lexeme_char : Lexing.lexbuf -> int -> char
 val lexeme_start : Lexing.lexbuf -> int
 val lexeme_end : Lexing.lexbuf -> int
 val lexeme_start_p : Lexing.lexbuf -> Lexing.position
 val lexeme_end_p : Lexing.lexbuf -> Lexing.position
 val new_line : Lexing.lexbuf -> unit
 val flush_input : Lexing.lexbuf -> unit
 val sub_lexeme : Lexing.lexbuf -> int -> int -> string
 val sub_lexeme_opt : Lexing.lexbuf -> int -> int -> string option
 val sub_lexeme_char : Lexing.lexbuf -> int -> char
 val sub_lexeme_char_opt : Lexing.lexbuf -> int -> char option
 type lex_tables = {
  lex_base : string;
  lex_backtrk : string;
  lex_default : string;
  lex_trans : string;
  lex_check : string;
  lex_base_code : string;
  lex_backtrk_code : string;
  lex_default_code : string;
  lex_trans_code : string;
  lex_check_code : string;
  lex_code : string;
 }
 val engine : Lexing.lex_tables -> int -> Lexing.lexbuf -> int
 val new_engine : Lexing.lex_tables -> int -> Lexing.lexbuf -> int
end