Initial data commit

Task/FASTA-format/OCaml/fasta-format.ocaml

@@ -0,0 +1,40 @@
+(* This program reads from the standard input and writes to standard output.
+ * Examples of use:
+ *    $ ocaml fasta.ml < fasta_file.txt
+ *    $ ocaml fasta.ml < fasta_file.txt > my_result.txt
+ *
+ * The FASTA file is assumed to have a specific format, where the first line
+ * contains a label in the form of '>blablabla', i.e. with a '>' as the first
+ * character.
+ *)
+
+let labelstart = '>'
+
+let is_label s = s.[0] = labelstart
+let get_label s = String.sub s 1 (String.length s - 1)
+
+let read_in channel = input_line channel |> String.trim
+
+let print_fasta chan =
+  let rec doloop currlabel line =
+    if is_label line then begin
+        if currlabel <> "" then print_newline ();
+        let newlabel = get_label line in
+        print_string (newlabel ^ ": ");
+        doloop newlabel (read_in chan)
+    end
+    else begin
+        print_string line;
+        doloop currlabel (read_in chan)
+    end
+  in
+  try
+    match read_in chan with
+    | line when is_label line -> doloop "" line
+    | _ -> failwith "Badly formatted FASTA file?"
+  with
+    End_of_file -> print_newline ()
+
+
+let () =
+  print_fasta stdin