Walkthrough of an RPL program for an RPN programmer

[Claudio L.]

(08-25-2018 01:35 PM)Maximilian Hohmann Wrote:  Hello!

As I am quoted in the original and really excellent (!) post of this thread I need to comment quickly... (have been away for work last week and couldn't do it earlier).

Having read the posting and the replies shows me several things:

1. RPL is not RPL, not even within HP. While I was away last week the postman brought me yet another HP-19BII (with an uncracked battery door) which supposedly is RPL based. The examples from above which I tried on that calculator did not work. Especially not replacing the "Enter" key with blank spaces between the numbers which I had never heard about before. But then that calculator is only RPL internally with an RPN user interface. Following the thread however I read that there are really siginificant differences between RPL on various HP calculators.

The RPL engine and basic language is the same on those various HP calculators. The libraries surrounding the RPL core are not: some models have a more complete set of commands than others. The UI can be anything you want, much like Ubuntu can have Gnome, KDE, XFCE, etc. running on top. It's still the same, just different UI, and different libraries.

(08-25-2018 01:35 PM)Maximilian Hohmann Wrote:  2. RPL experts are not RPL experts, at least every one seems to use it in his own special way. Which makes RPL a very versatile tool but even harder to understand for laypersons. Because not only does one need a good understanding of the underlying principle/paradigm but one must be able to follow the thought patterns of the programmer. And all based on some extremely abbreviated and cryptic syntax. The best example for that is the expression « → a 'a+a' » of which, even after having read the whole thread, I still don't have the faintest idea what it might do.

This is true for many languages! I consider myself seasoned in C++, and I still have no clue how those templates and meta-templates could possibly work. But I don't blame the language, and keep coding in C++ "in my own way".

(08-25-2018 01:35 PM)Maximilian Hohmann Wrote:  3. RPL is definitely not for the occasional user.
4. Some RPL implementations are exrtemely powerful. 2500 built in functions. Impressive! But who remembers all those when he needs them? I certainly couldn't and the manuals don't make it very easy to find them either. There must be a reason why RISC has become the standard with microprocessors now: Keep it simple and keep the users in the loop.

And this is also true for many other languages! Knowing C or C++ doesn't mean you can code a simple hello world with Qt, or MFC, or GTK, or ...[name your tookit here]...
All those toolkits are massive and impressive, and equally difficult to master. I agree manuals don't help much, but that's also true for the aforementioned toolkits. There's more tutorials just because there's more people using them, but that's it.

I love that to learn Lua you need to read only 36 pages of the manual to fully understand and master the language. It's that simple. But then when you want to code anything serious, you use libraries with hundreds of API functions you need to learn on your own, so it ends up being the same as all other languages.