A OCaml module for manipulating unlimited register machines
Changed the command line paramenters
Also introduced the Urm.of_list function to help parsing of the command line arguments
5 files changed, 97 insertions, 81 deletions
| Status | File Name | N° Changes | Insertions | Deletions |
| Modified | docs.pdf | 0 | 0 | 0 |
| Modified | main.ml | 141 | 69 | 72 |
| Modified | urm.1 | 27 | 19 | 8 |
| Modified | urm.ml | 4 | 4 | 0 |
| Modified | urm.mli | 6 | 5 | 1 |
diff --git a/main.ml b/main.ml @@ -1,89 +1,86 @@ open List let usage () = - Printf.printf "USAGE: urm [-i ITERS] REGISTERS FILE\n"; + Printf.printf "USAGE: urm FILE [-i ITERS] [-RN=V...] [-RN...] \n"; Printf.printf "See urm.1 for additional information\n" let default_max_iters = 1000 -(** An equivalent to Haskell's [sequence] *) -let sequence (xs : 'a option list) : 'a list option = - let f x acc = Option.bind x (fun x -> Option.map (List.cons x) acc) - in List.fold_right f xs (Some []) - (** Execute the program from [file] with initial register values given by [regs] and the maximum number of allowed iterations set to [iters] *) -let main iters regs file = +let main iters init_m regs_prints file = let contents = really_input_string file (in_channel_length file) in try - let program = Urm.parse contents - and regs_fn i = if i < Array.length regs then regs.(i) else 0 - in - match Urm.nexec iters program (Urm.of_registers regs_fn) with - | Some m -> - let regs_strs = - Urm.register m - |> List.init (Array.length regs) - |> List.map (Printf.sprintf "%d") - in Printf.printf "%s\n" (String.concat " " regs_strs) - | None -> - Printf.eprintf - "ERROR: the input program did not halt after %d iterations\n" - iters; - Printf.eprintf "The input program may not halt\n"; - exit 1 - with Urm.Syntax_error err -> Printf.eprintf "ERROR: %s\n" err - - -(** Initial parsing of the command-line arguments: get the strings out *) -let (iters, regs_str, filepath) : int * string * string = - let parse_iters iters_str = - match int_of_string_opt iters_str with - | Some n when n > 0 -> - n - | Some n -> - Printf.eprintf - "ERROR: negative number of maximum iterations provided: %d\n" n; - Printf.eprintf "Expected a positive integers\n"; - usage (); - exit 1 + let program = Urm.parse contents in + match Urm.nexec iters program init_m with + | Some m -> + List.iter (fun n -> Printf.printf "R%d = %d\n" n (Urm.register m n)) + regs_prints | None -> Printf.eprintf - "ERROR: invalid number of maximum iterations provided: '%s'\n" - iters_str; - Printf.eprintf "Expected a positive integers\n"; - usage (); - exit 1 - in - match Sys.argv with - | [| _ ; "-i" ; iters_str ; regs ; filepath |] -> - (parse_iters iters_str, regs, filepath) - | [| _ ; regs ; filepath |] -> - (default_max_iters, regs, filepath) - | argv when Array.length argv < 3 -> - Printf.eprintf "ERROR: not enought arguments provided\n"; - usage (); - exit 1 - | _ -> - Printf.eprintf "ERROR: invalid arguments provided\n"; - usage (); + "ERROR: the input program did not halt after %d iterations\n" + iters; + Printf.eprintf "The input program may not halt\n"; exit 1 + with Urm.Syntax_error err -> Printf.eprintf "ERROR: %s\n" err -(** Parse the initial values of the registers as a list of ints separated by - spaces *) -let regs = - let regs = List.filter ((<>) "") (String.split_on_char ' ' regs_str) - in - match sequence (List.map int_of_string_opt regs) with - | Some regs -> - regs - | None -> - Printf.eprintf - "ERROR: invalid initial values for the registers provided: '%s'\n" - regs_str; - Printf.eprintf "Expected a list of integers separated by spaces\n"; - usage (); - exit 1 +(** Parses the command-line arguments concerning registers. + returns [(regs_vals, regs_prints)], where [regs_vals] is the list of pairs + encoding the initial values of the machine, and [regs_prints] is the list + of registers that should be printed at the end of execution. *) +let parse_regs (regs : string list) : (int * int) list * int list = + let rec fail reg = + Printf.eprintf "ERROR: invalid arguments provided: %s\n" reg; + usage (); + exit 1 + and f reg (acc_vals, acc_prints) = + if not (String.starts_with ~prefix:"-R" reg) then fail reg + else let reg' = String.sub reg 2 (String.length reg - 2) in + match String.split_on_char '=' reg' with + | [reg_n] -> + (match int_of_string_opt reg_n with + | Some reg_n -> (acc_vals, reg_n :: acc_prints) + | None -> fail reg) + | [ reg_n ; reg_val ] -> + (match (int_of_string_opt reg_n, int_of_string_opt reg_val) with + | (Some reg_n, Some reg_val) -> + ((reg_n, reg_val) :: acc_vals, acc_prints) + | _ -> fail reg) + | _ -> fail reg + in List.fold_right f regs ([], []) + +(** Parses the [-i] command line argument *) +let parse_iters (iters_str : string) : int = + match int_of_string_opt iters_str with + | Some n when n > 0 -> + n + | Some n -> + Printf.eprintf + "ERROR: negative number of maximum iterations provided: %d\n" n; + Printf.eprintf "Expected a positive integers\n"; + usage (); + exit 1 + | None -> + Printf.eprintf + "ERROR: invalid number of maximum iterations provided: '%s'\n" + iters_str; + Printf.eprintf "Expected a positive integers\n"; + usage (); + exit 1 + +(** Parses all command line arguments *) +let (iters, init_m, regs_prints, filepath) : int * Urm.t * int list * string = + match Array.to_list Sys.argv with + | _ :: file_path :: "-i" :: iters_str :: regs -> + let (reg_vals, reg_prints) = parse_regs regs in + (parse_iters iters_str, Urm.of_list reg_vals, reg_prints, file_path) + | _ :: file_path :: regs -> + let (reg_vals, reg_prints) = parse_regs regs in + (default_max_iters, Urm.of_list reg_vals, reg_prints, file_path) + | _ -> + Printf.eprintf "ERROR: not enought arguments provided\n"; + usage (); + exit 1 (** Try to open the file with the contents of the program *) let file = @@ -93,5 +90,5 @@ let file = Printf.eprintf "ERROR: %s\n" err; exit 1 -let () = main iters (Array.of_list regs) file +let () = main iters init_m regs_prints file
diff --git a/urm.1 b/urm.1 @@ -6,9 +6,9 @@ .\" .\" Unlimited Register Machine simulator .\" -.\" Copyright (C) 2021 Pablo +.\" Copyright (C) 2022 Pablo .\" Free use of this software is granted under the terms of the GPL-3.0 License -.TH "MAN" "1" "2021-12-11" "\ \&" "\ \&" +.TH "MAN" "1" "2023-03-19" "\ \&" "\ \&" .ie \n(.g .ds Aq \(aq .el .ds Aq ' .ss \n[.ss] 0 @@ -33,14 +33,25 @@ A simple Unlimited Register Machine (URM) simulator .SH "USAGE" .sp -\fBurm\fP [-i ITERS] REGISTERS FILE +\fBurm\fP \fIFILE\fP [-i \fIITERS\fP] [-R\fIN\fP=\fIV\fP...] [-R\fIN\fP...] .SH "OPTIONS" .sp -\fB-i ITERS\fP -.RS 4 Sets the maximum number of iterations allowed to \fBITERS\fP: an arbitrary +\fB-i\fP \fIITERS\fP +.RS 4 +Sets the maximum number of iterations allowed to \fIITERS\fP: an arbitrary program may not halt for a given input and this option configures how much instructions is the machine allowed to run before failing with an error. -Defaults to \fB1000\fP +Defaults to \fI1000\fP +.RE +.sp +\fB-R\fP\fIN\fP=\fIV\fP +.RS 4 +Sets the initial value of the \fIN\fP-th register to \fIV\fP +.RE +.sp +\fB-R\fP\fIN\fP +.RS 4 +Prints the value of the \fIN\fP-th register at the end of execution .RE .SH "AUTHORS" .sp @@ -50,8 +61,8 @@ Defaults to \fB1000\fP .SH "RESOURCES" .sp \fBGit source repository:\fP \c -.URL "https://git.pablopie.xyz/caml\-urm/README.html" "" "" +.URL "https://git.pablopie.xyz/caml\-urm/" "" "" .SH "COPYING" .sp -Copyright (C) 2021 Pablo. +Copyright (C) 2023 Pablo. Free use of this software is granted under the terms of the GPL\-3.0 License.
diff --git a/urm.ml b/urm.ml @@ -20,6 +20,10 @@ let of_registers f = registers = f } +let of_list xs = + let f acc (reg_n, reg_val) = fun n -> if n = reg_n then reg_val else acc n + in xs |> List.fold_left f (fun _ -> 0) |> of_registers + let zeros = of_registers (fun _ -> 0) let register m = m.registers
diff --git a/urm.mli b/urm.mli @@ -37,11 +37,15 @@ type instruction = type t (** An alias for {! t } *) -type machine +type machine = t (** Returns a machine whose register values are given by a function. *) val of_registers : (int -> int) -> machine +(** Returns a machine whose registers are given by the pairs in a list. All + other registers are zero initialized. *) +val of_list : (int * int) list -> machine + (** [register m i] returns the value of the [i]-th register of [m]. *) val register : machine -> int -> int