reviving thread...
In the back of my mind I knew that the Engines, at least at one time, at least on Unix with Display Postscript screen rendering (so NeXT,Sun,Irix,etc.) had support for EPS Objects, but digging through the IDE and seeing references to that, newly reminded me of this fact so I decided to try it on NeXT modern descendant, macOS, just for the hell of it...
Create a new stack and then put this into the message box:
It does indeed create an EPS object, which the Property Inspector claims is "No Object Selected" even though I can clearly see it is an object, it is selected, and I can edit its script and use it like a graphic object (responds to mouseUp/Down).
The only related syntax in the dictionary I could find indicates it was used like so:
set postscript of EPS "TestEPS" to field "PostScriptCode"
I tried this out, putting some very basic PostScript commands in field "PostScriptCode". Which sadly did nothing.
The Cairo 2D drawing library that is used by the engines does still support Postscript, I believe Skia, used in Extensions for widget canvas drawing, can support PS as well. Interestingly, when I move the position of this EPS Object on my stack, while moving it, it renders an 'X' inside the object rect, as seen in page layout programs such as InDesign, QuarkXpress, etc. It's almost like the support for EPS is still in there but it's been abandoned, probably because these days there is also SVG and PDF for resolution independent graphics. Maybe it could've been repurposed to support those too, rename it Encapsulated 'Picture' Stuff (lol) object or just make it an synonym for a 'Picture' object type, as was briefly discussed when they were first adding color SVG Support to the engines ( which wound up just using existing 'image' object vis drawingSvgCompile() ).