Can we have RPN back?

[Han]

(02-10-2014 04:26 PM)John R. Graham Wrote:  I think we mostly agree. But I think it's confusing to say RPL vs. RPN: it's apples vs. oranges. RPL has never been a term that described the data entry mode. If it doesn't start with « then it isn't (User) RPL.

- John

It's not apples and oranges -- if anything, it's a Washington apple vs a Granny Smith apple :-). I agree that RPL is not _commonly_ used to refer to data entry -- but only because RPL was never really used as a common term, period. Again, to quote Wickes: RPL was never particularly intended to be a public term.

Here's a link showing Richard Nelson referring to RPL as if it were a new method of entry (first sentence). He later calls it "Entry RPN"
http://h20331.www2.hp.com/hpsub/download...%20V5b.pdf

From our very own museum, an article about the "versions" of RPN.

http://www.hpmuseum.org/rpnvers.htm

As for why I personally refer to them as RPL vs RPN, it's actually related to your comment about « and UserRPL. The suggestion that « is required in order to be called (User)RPL is incorrect. If you take an HP48 and press [RightShift] [Alpha] followed by 3 [SPC] 2 + 9 / -- that's RPL input. It's a program without the « delimiter -- all sitting in the command line waiting for you to press ENTER before executing. You can certainly do more complex "programs" than this. In fact, the command line itself is a program editor. The evolution from RPN to RPL was such that the command line was previously limited to a single entry (either a number or a single command via a key-press) in the "RPN" machines can now handle a full-blown program in the "RPL" machines. This had mainly to do with the fact that the "command line" was also the first level of the stack on the RPN machines.

Granted, most users still only used RPL machines like they did RPN machines. That is, they would press 3 ENTER 2 + 9 / to get the same result. But that is very different from typing 3 2 + 9 / (also using only keystrokes) in the command line.

But yes, I think we mostly agree.