RPL (programming language): Difference between revisions

Revision as of 13:07, 23 October 2023

Revision as of 21:50, 27 October 2023

Line 27:

RPL is a [[structured programming]] language based on RPN, but equally capable of processing [[infix notation|algebraic]] expressions and formulae, implemented as a [[threaded code|threaded interpreter]].<ref name="RPL3"/> RPL has many similarities to [[Forth (programming language)|Forth]], both languages being [[stack-oriented programming language|stack]]-based, as well as the list-based [[LISP]]. Contrary to previous HP RPN calculators, which had a fixed [[4-level RPN|four-level stack]], the [[dynamic RPN stack|dynamic stack]] used by RPL is only limited by available [[random-access memory|RAM]], with the calculator displaying an error message when running out of memory rather than silently dropping arguments off the stack as in fixed-sized RPN stacks.<ref name="Wessman_2016"/>

RPL originated from HP's [[Corvallis, Oregon]] development facility in 1984 as a replacement for the previous practice of implementing the [[operating systems]] of calculators in [[assembly language]].<ref name="RPLMAN"/> The first calculator utilizing it internally was the HP-18C and the first calculator making it available to users was the HP-28C, both from 1986.<ref name="Wickes_1987"/><ref name="RPLMAN"/> The last pocket calculator supporting RPL, the HP 50g, was discontinued in 2015.<ref name="Kuperus_2015_1"/><ref name="Kuperus_2015_2"/><ref name="Wessman_2015"/> However,<!-- an [[Mobile app|app]] is available for [[Android (operating system)|Android]], go49gp[https://play.google.com/store/apps/details?id=o2s.emul.hp49gp&hl=en_US], which emulates the HP 49g+/50g and will run RPL programs. --> multiple emulators that can emulate HP's RPL calculators exist that run on a range of operating systems, and devices, including iOS and Android smartphones. There are also a number of community projects to recreate and extend RPL on newer calculators, like [[newRPL]]<ref name="newRPL"/> or [[DB48X]],<ref name="db48x"/>, which may add features or improve performance.<ref name="newRPL-speed"/>.

==Variants==