Let’s start with a quick recap for those of you who are just tuning in (and for those who have been tuned in for a while but are likely very lost):

• In the late 80s, Psion developed their own message-passing Object Oriented C dialect with its own markup language. They did this because Psion be Psion-ing. This is a recurring theme.
• CTRAN.EXE, a 16-bit DOS app, is Psion’s OO preprocessor. It takes class declaration files using this OO markup language (called “category files” by no one but Psion – see the previous point) and translates them into C and Turbo Assembler code.
• The C generator in CTRAN.EXE is rudimentary but very reliable.
• The TASM generator is, shall we say, less optimal. There are bugs. Sometimes it crashes. I’m convinced no one actually used it.

Here’s an example category file. If you’ve written parsers before, you’ll enjoy trying to wrap your head around this format!

At the beginning of 2024, I ragequit reading about Psion’s proprietary Object Oriented C.

This was unexpected, but I should have seen it coming.

Near the end of the previous November, I made an announcement on social media. I was going to start working on a new word processor for Psion’s 16-bit portable machines. I’d been working on Psion-related projects since September 2018, focusing on the SIBO/EPOC16 platform. Writing a replacement for Psion Word was one of the first ideas I’d had. So, as I’d spent the latter half of 2023 bouncing between projects and never quite settling, I decided that now was the time. It was to be called Vine, a nod to both the codename of the Psion Siena and the Vi-like bindings I was hoping to include in its feature set.