[ANN] Simple RPN Calculator on RevOnline

[DunbarX at aol.com]

Andre.

The whole point of registers is that data entry is naturally terminated by 
either an "enter" or an operator. The data is loaded, and waits for the user 
to command it. This is unlike an algebraic (or operator prefix) system 
where the operator is entered between the operands, and therefore the process is 
locked into a prescribed state. You cannot change your mind, and add, 
instead of multiply, those two numbers you are interested in. The four register 
stack permits any number of levels of nested, complex chain calculations. 
This requires a separate temporary register in a prefix system.

But you know all that. I just think that a register based gadget would be 
easier to author than any other, and you could make it so those registers are 
visible, if you wanted to. Like that calculator I cannot remember...

Craig


In a message dated 10/13/10 4:47:53 PM, andre at andregarzia.com writes:


> Craig,
> 
> Just added a new revision to RevOnline, now there is a negate button and 
> the
> minus sign behave as expected (by executing the operation)
> 
> the switch and rolldown button would depend on me having registers which I
> don't right now. There is "swp" which swaps the last two entries in the
> stack.
> 
> Will find out how hard it is to have some HP like registers.
>