regex-redux OCaml #3 program

(* The Computer Language Benchmarks Game
 * https://salsa.debian.org/benchmarksgame-team/benchmarksgame/
 *
 * regex-dna program contributed by Christophe TROESTLER
 * updated by Roman Kashitsyn: use Bytes instead of String
 * updated by Gaëtan Dubreil: use the Re library and parallelize processing
 *)

open Printf

let variants = ["agggtaaa|tttaccct";          "[cgt]gggtaaa|tttaccc[acg]";
                "a[act]ggtaaa|tttacc[agt]t";  "ag[act]gtaaa|tttac[agt]ct";
                "agg[act]taaa|ttta[agt]cct";  "aggg[acg]aaa|ttt[cgt]ccct";
                "agggt[cgt]aa|tt[acg]accct";  "agggta[cgt]a|t[acg]taccct";
                "agggtaa[cgt]|[acg]ttaccct"]

let subst = ["tHa[Nt]", "<4>"; "aND|caN|Ha[DS]|WaS", "<3>";
             "a[NSt]|BY", "<2>"; "<[^>]*>", "|"; "\\|[^|][^|]*\\|", "-"] 

(* Read all of a redirected FASTA format file from stdin. *)
let file_data, file_length =
  let b = Buffer.create 0xFFFF in
  let s = Bytes.create 0xFFF in
  let r = ref 1 in
  while !r > 0 do
    r := input stdin s 0 0xFFF;
    Buffer.add_substring b (Bytes.unsafe_to_string s) 0 !r
  done;
  (Buffer.contents b, Buffer.length b)

(* Remove FASTA sequence descriptions and all linefeed characters.  *)
let dna = Re.replace_string (Re.Pcre.regexp ">.*\n|\n") "" file_data
let code_length = String.length dna

(* Count matches of [re]. *)
let count re s =
  let re = Re.Pcre.regexp re in
  let i = ref 0 in
  let n = ref 0 in
  try
    while true do
      let grps = Re.exec ~pos:!i re s in
      i := Re.Group.stop grps 0;
      incr n
    done;
    assert false
  with Not_found -> !n

let () =
  if Unix.fork() = 0 then (
    List.iter (fun re -> printf "%s %i\n" re (count re dna)) variants;
  )
  else (
    let b = ref dna in
    List.iter (fun (re, s) ->
        b := Re.replace_string (Re.Pcre.regexp re) s !b) subst;

    ignore(Unix.wait());
    printf "\n%i\n%i\n%i\n" file_length code_length (String.length !b)
  )
    

NOTES:
64-bit Ubuntu quad core
OCaml native-code
version 5.1.1


 Sat, 09 Mar 2024 20:39:39 GMT

MAKE:
mv regexredux.ocaml-3.ocaml regexredux.ocaml-3.ml
~/.opam/5.1.1/bin/ocamlopt -noassert -unsafe -fPIC -nodynlink -inline 100 -O3 -I /home/dunham/.opam/5.0.0/lib/re unix.cmxa re.cmxa -ccopt -march=ivybridge regexredux.ocaml-3.ml -o regexredux.ocaml-3.ocaml_run
File "regexredux.ocaml-3.ml", line 1:
Error: "/home/dunham/.opam/5.0.0/lib/re/re.cmi"
       is not a compiled interface for this version of OCaml.
It seems to be for an older version of OCaml.
make: [/home/dunham/all-benchmarksgame/2000-benchmarksgame/nanobench/makefiles/u64q.programs.Makefile:357: regexredux.ocaml-3.ocaml_run] Error 2 (ignored)
rm regexredux.ocaml-3.ml

0.65s to complete and log all make actions

COMMAND LINE:
 ./regexredux.ocaml-3.ocaml_run 0 < regexredux-input50000.txt

MAKE ERROR