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newRPL: [UPDATED April 27-2017] Firmware for testing available for download
10-29-2015, 12:38 PM (This post was last modified: 10-29-2015 12:40 PM by Claudio L..)
Post: #114
RE: newRPL: [UPDATED Oct-19-2015] Firmware for testing available for download
(10-28-2015 02:30 PM)Han Wrote:  Waxing philosophical:

You're using an algebraic expression. That's not very RPN-like in my opinion. Now, I understand that it may be easier to understand the content of a program if a formula is written algebraically rather than using RPN to build the expression.

From more practical perspective: expressions are objects in the RPL world, they aren't against it. We are here defining the foundations of a brand new CAS that will operate and modify those expressions automatically. The user needs a way to pass information to the CAS on what should or should not be evaluated immediately.
One way to do it is through text in the expression itself (I don't claim is the only way or the best way).

(10-28-2015 02:30 PM)Han Wrote:  However, we can add comments with @ and comments are not removed. Or are they removed?
I didn't implement comments yet, but yes, we agreed that one flag will control whether the @ comments are kept or removed during compile. We also agreed that @@ comments would be permanent and override any flag settings.

However, the objective of the trailing dot is not to make the code readable by using expressions instead or RPL commands. Code beauty is merely a byproduct.
The real objective is to pass some information to the CAS, to tell we want that variable replaced immediately, or in other words, that the symbol is secondary and we are not interested in wasting time manipulating it.

(10-28-2015 02:30 PM)Han Wrote:  In the HP48, one could type 'X.' and get an 2-character identifier whose name is X followed by a period. This would break in newRPL.
The trailing dot was used in the 50g to distinguish integers from reals, which was already changed in newRPL to define whether numbers should be operated upon immediately on a symbolic (even if the operation introduces an error, hence the "approximated" name) or kept as-is (exactly as typed, or operated upon using only exact operations).
I think I'd rather have consistency in newRPL meaning of the dot than trying to keep a relatively unused feature of the old RPL.
If you have an old program using variables that end in dots, it's trivial to replace with 'Xdot' for example, before passing the source code to newRPL.
Just converting from HP48 codepage to Unicode will be more difficult than that.
I don't think it causes a serious incompatibility.

(10-28-2015 02:30 PM)Han Wrote:  EDIT: just to be clear -- I'm not opposed to the feature itself (I think it's useful) but I would rather it be implemented in a way that is compatible with old RPL code.

I know, and I like these discussions, it's the very reason why I write these ideas for public input. While I may disagree with you on some point, during this discussion you brought up an interesting new feature: the variable content preview. I like that and will be implemented soon, we just have to find the right key combination to bind it to. I'd like for it to work always, not just in ALG mode.
I'm thinking the long-press will work, but I'd have to move the VAR menu hide/show feature to another key, no big deal (but it was quite intuitive to have it in VARS).
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RE: newRPL: [UPDATED Oct-19-2015] Firmware for testing available for download - Claudio L. - 10-29-2015 12:38 PM

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