Help, wierd existence_error message from previously working code!
I am stuck with a really wierd problem around some code that used to work just fine and I am at a loss to explain what is happening. A long time back I published on github a comprehensive binding to SDL2 for gprolog, it all worked on ubuntu and OSX just fine.
A year or two down the line, I checked out the code, it built first time but it is raising existence_error-s on code that exists BUT ARITY IS ZERO.
I have an event loop predicate that calls itself until you hit the ESC key... here is what it looks like trying to run the fonttest predicate: