cwfoo · May 21, 2022 06:45
diff --git a/polyml-syntax-check.sml b/polyml-syntax-check.sml
 (* Check for syntax errors and type errors in a Standard ML file without
 * executing the program. Tested in Poly/ML 5.9 on Ubuntu 20.04.
 *
 * To check for the existence of errors in a Standard ML file using Poly/ML, it
 * is sufficient to use `PolyML.compiler (TextIO.input1 inStream, [])`. However,
 * that will not show line and column numbers when there are errors or warnings.
 * This program adds line and column numbers to the error and warning messages.
 *
 * Usage:
 *   poly --script this-file.sml file-to-check.sml
 *
 * Behavior:
 *   * Prints warnings and errors to standard output.
 *   * Exits with exit code 1 if there are errors, exits with exit code 0
 *     otherwise.
 *
 * To print to standard error instead of standard output, add this to the
 * compiler parameter list in the call to PolyML.compiler:
 *   PolyML.Compiler.CPOutStream (fn s => (TextIO.output (TextIO.stdErr, s);
 *                                         TextIO.flushOut TextIO.stdErr))
 * *)

 fun getLineChars inStream =
  (* Limitation: TextIO.inputLine will raise the "Size" exception if the line is
   * longer than String.maxSize. *)
  case TextIO.inputLine inStream of
    NONE => NONE
  | SOME s => SOME (explode s)

 fun checkFile filePath =
  let
    val lineNum = ref 0
    val colNum = ref 0
    val curLine = ref []
    val ins = TextIO.openIn filePath
    fun getChar () =
      case !curLine of
        [] =>
          (case getLineChars ins of
             NONE => NONE
           | SOME (c::cs) =>
               (curLine := cs;
                lineNum := !lineNum + 1;
                colNum := 1;
                SOME c)
           | SOME [] =>
               (lineNum := !lineNum + 1;
                getChar ()))
      | (c::cs) =>
          (curLine := cs;
           colNum := !colNum + 1;
           SOME c)
  in
    (ignore o PolyML.compiler)
      (getChar, [PolyML.Compiler.CPFileName filePath,
                 PolyML.Compiler.CPLineNo (fn () => !lineNum),
                 PolyML.Compiler.CPLineOffset (fn () => !colNum)])
  end

 val () = case CommandLine.arguments () of
           ["--script", _, fileToCheck] => checkFile fileToCheck
         | _ => raise (Fail "Invalid command line arguments")
	(* Check for syntax errors and type errors in a Standard ML file without
	* executing the program. Tested in Poly/ML 5.9 on Ubuntu 20.04.
	*
	* To check for the existence of errors in a Standard ML file using Poly/ML, it
	* is sufficient to use `PolyML.compiler (TextIO.input1 inStream, [])`. However,
	* that will not show line and column numbers when there are errors or warnings.
	* This program adds line and column numbers to the error and warning messages.
	*
	* Usage:
	* poly --script this-file.sml file-to-check.sml
	*
	* Behavior:
	* * Prints warnings and errors to standard output.
	* * Exits with exit code 1 if there are errors, exits with exit code 0
	* otherwise.
	*
	* To print to standard error instead of standard output, add this to the
	* compiler parameter list in the call to PolyML.compiler:
	* PolyML.Compiler.CPOutStream (fn s => (TextIO.output (TextIO.stdErr, s);
	* TextIO.flushOut TextIO.stdErr))
	* *)

	fun getLineChars inStream =
	(* Limitation: TextIO.inputLine will raise the "Size" exception if the line is
	* longer than String.maxSize. *)
	case TextIO.inputLine inStream of
	NONE => NONE
	\| SOME s => SOME (explode s)

	fun checkFile filePath =
	let
	val lineNum = ref 0
	val colNum = ref 0
	val curLine = ref []
	val ins = TextIO.openIn filePath
	fun getChar () =
	case !curLine of
	[] =>
	(case getLineChars ins of
	NONE => NONE
	\| SOME (c::cs) =>
	(curLine := cs;
	lineNum := !lineNum + 1;
	colNum := 1;
	SOME c)
	\| SOME [] =>
	(lineNum := !lineNum + 1;
	getChar ()))
	\| (c::cs) =>
	(curLine := cs;
	colNum := !colNum + 1;
	SOME c)
	in
	(ignore o PolyML.compiler)
	(getChar, [PolyML.Compiler.CPFileName filePath,
	PolyML.Compiler.CPLineNo (fn () => !lineNum),
	PolyML.Compiler.CPLineOffset (fn () => !colNum)])
	end

	val () = case CommandLine.arguments () of
	["--script", _, fileToCheck] => checkFile fileToCheck
	\| _ => raise (Fail "Invalid command line arguments")