Display an em-dash in .z5 format (Frotz, Fizmo, Parchment)

I know the Z-machine can do Unicode, sort of; but I’m bogging down on the details. How do I print an em-dash (Unicode U+2014), assuming I’m using Inform 6? Does the ability to display Unicode also depend on my interpreter? I’m most concerned with Parchment (ZVM, I think), but also interested in Frotz and/or Fizmo in a Linux terminal (UTF-8).

It’s apparently not as easy as print "@{2014}"

Printing Unicode will depend on the capabilities of your interpreter and its display environment, including what fonts it has access to, but these days I would expect most interpreters to handle it pretty well.

print "@{2014}"

For this to work the character needs to be entered into the Zcharacter table, which has a few free slots (though not many). This would involve having a declaration at the top of the Inform 6 source like

Zcharacter table + '@{2014}';

It’s often easier to just use the @print_unicode opcode from the Z-Machine 1.0 specification, like this:

@print_unicode $2014;

There’s a little test file (Unicode.z5 and Unicode.inf) I wrote for testing such things that comes with Windows Frotz, which might help. Also worth reading is Roger Firth’s Inform 6 FAQ entry on Unicode handling: http://www.firthworks.com/roger/informfaq/aa20.html

Web interpreters will have the best unicode support because browsers automatically find fonts with the characters you need if your normal font doesn’t have them.

Desktop interpreters can do this too: Windows Frotz uses Internet Explorer’s MLang interface to achieve the same effect.

Awesome! thanks! I had been trying almost exactly your first method, but without the “+” in the Zcharacter line. (Which now doesn’t seem to make a difference.) Looks like Linux “frotz” doesn’t do Unicode; everything comes through as question marks. But Linux “fizmo” does the right thing, and so does Parchment, via either method (Zcharacter plus “@{2014}”, or @print_unicode).

Fortunately, Roger Firth’s FAQ provides the solution! :slight_smile:

[ Unicode c substitute exist;
    if (0-->31 < 1) { print (string) substitute; return; }
    @check_unicode c -> exist;
    if (exist & $0001) @print_unicode c;
    else print (string) substitute;

Called as Unicode($2014, “–”), this does what I want.