Free42: Unlimited-length strings and other type extensions

[Thomas Okken]

Filesystem access is not out of the question. A fork with HP-IL extensions does exist: https://github.com/jch42/free42

I have always been reluctant to add a lot of functionality to Free42 precisely because I prefer the elegance of the original myself, but then again, useful but lightweight additions, that don't add significantly to the footprint and don't get in the way in the UI, have happened from time to time, and I think FUNC and RTNYES/RTNNO/RTNERR belong in that category. The big stack seems like a bit of a borderline case, because it did require a lot of code changes, but I felt it was OK to add to the basic Free42 because despite all the code changes, it is nonetheless also quite lightweight.

But with Free42+, the whole idea is to go nuts and put in everything that seems useful, and if that means it ends up being a kind of 48S with RPN, why not?