I still am wondering how error handling should be done in pony, it only tells you an error has happend, not what has caused it or what kind of error happend.
A partial function is where you can't compute a result based on the input.
If you need to know what went wrong (because more than one thing might have gone wrong and that needs to be communicated), you can use a union type for the result and match accordingly (as you would in Rust as an example).
If you have used it and have any ideas on what you'd like to see there, feel free to drop by Zulip!
"Makes the files package better" is something that has been on a "list of things to improve" for a long time.