Ace was developed as a part of the Structured Information Manager (SIM), a commercial product currently available in Australia and the US. The Ace scripting language is used throughout SIM for specifying indexing rules in the SIM database server, for developing web applications in the SIM web server, and so on.

A free version of the Ace scripting language has been released to the public allowing scripts to be run from the command line. As Ace is part of a commercial product, source code is not available, only precompiled executables.

The highlights of Ace are:

• Extensive library of SGML and XML manipulation functions
• Strongly typed
• Object oriented syntax
• Efficient run time evaulator
• Readable code (compared to some alternative SGML manipulation products)
• Variables, procedures, functions, arrays, associations, automatic garbage collection, user defined types...

Example code to extract all sections within chapters that have a title is:

   doc.all("CHAPTER").children("SECTION").(n: n.children("TITLE").exists())

A free download of Ace is available, as well as a mailing list. Some more sample code is also available.

Factorial

   #
   # Return the factorial of 'n'.
   #
   function Integer n.factorial() => Integer
   begin
      if n < 1 then
         throw "n must be >0 for factorial (was " + n.toString() + ")";
      end;
      integer r := 1;
      for Integer i := 1; i <= n; i++; do
         r := r * i;
      end;
      return r;
   end;
      
   #
   # Main program
   #
   begin
      StringBuffer s := new StringBuffer();
      try
         s << "5 factorial is " << 5.factorial() << "\n";
         s << "0 factorial is " << 0.factorial() << "\n";
      catch String message
         s << "oops:" << message << "\n";
      end;
      return s;
   end

SGML Normalisation

   import ConsoleAccess;
 
   begin
      if argv.size() <> 2 then
         cerr << "usage: " + argv[0] + " file.sgm\n";
         exit(1);
      end;
      SgmlEntityManager entMgr := new SgmlEntityManager("file");
      SgmlEventStream s := new SgmlEventStream(entMgr, argv[1], "SGML");
      SgmlEvent event;
      String text := entMgr.entity(argv[1]).content();
      while (event := s.nextEvent()).type() <> "end" do
         cout << event.toString();
      end;
      cout << "\n";
      return "";
   end

SGML Tree Walking

   import ConsoleAccess;
 
   begin
      if argv.size() < 2 then
         cerr << "usage: " + argv[0] + " file.xml ...\n";
         exit(1);
      end;
      SgmlEntityManager entMgr := new SgmlEntityManager("file");
      argv.remove(0);
      foreach fileName in argv do
         String fileContents := readFile(fileName);
         SgmlEntity ent := new SgmlEntity(fileName, fileContents);
         SgmlDocument doc := new SgmlDocument(entMgr, ent, "XML");
         foreach title in doc.root().all("CHAPTER").children("SECTION")
                                     .children("TITLE").toIndexString() do
            if title.matches("XML") then
               cout << fileName << ": " << title << "\n";
            end;
         end;
      end;
      return "";
   end