(* File input handling *)

structure Read_Input : READ_INPUT =
struct
(* line number, contents of the line *)
type lineinput = {line: int, contents: char list};
(* File name, and a list of line descriptors *)
type file_input_stream = {filename: string, lines: lineinput list};

fun input_file (a : string) =
    let
	val inputstream = TextIO.openIn a;
	fun input_lines (stream : TextIO.instream, linenum : int) =
	    if TextIO.endOfStream(stream) then (TextIO.closeIn stream; nil)
	    else
		{line = linenum, contents = (explode (TextIO.inputLine stream))}::input_lines (stream, linenum + 1);
    in
	{filename = a, lines = (input_lines (inputstream, 1))}
    end;

end;

type lineinput = {line: int, contents: char list};
type file_input_stream = {filename: string, lines: lineinput list};