*UPDATE: *
I guess it was as simply as just including a blank function playdate.update() function in the main.lua No more error.
I am running on a Mac. I'm nearly a complete beginner — not to coding per se, but to this sort of environment. So I'm not even terribly comfortable with a command line.
BUT! Things were running smoothly when I first installed everything.
Now every time I compile and run the .pdx on the simulator I get the error
"No such function 'update'"
Even if it's just a simple print statement.
I've tried removing all but the simplest lua code but it still seems to be trying to run this function that I can't tell where it even exists. What could I do to reset this?