Talk:RPL (programming language)

message: There is a simple postfix-based way to implement if/then/else structures, which RPN purists would prefer.
The following example uses the IFT ("if-then") function to pop an object from the bottom of the stack, and if it is equal to 1, replace it with "One":
 « 1 == "One" IFT »
The following example uses the IFTE ("if-then-else") function to pop an object from the bottom of the stack, and if it is equal to 1, replace it with "One", otherwise replace it with "Not one":
 « 1 == "One" "Not" IFTE »
These structures can of course be nested. Both of the following examples pop an object from the bottom of the stack, and replace it with "One", "Less", or "More", depending on whether it is equal to, less than, or greater than 1.
 «
   DUP 1 ==
   « DROP "One" »
   « 1 < "Less" "More" IFTE »
   IFTE
 »
 
 « -> x
   «
     x 1 ==
     "One"
     « x 1 < "Less" "More" IFTE »
     IFTE
   »
 »
Tony.
:I added a section for IFT/IFTE, using some of the content you've placed here.  --MatthewMastracci 19:27, 12 May 2005 (UTC)
thread_title: Postfix conditional structures

message: The recently-added content about the REALITY Programming Language is a different subject altogether. It should be moved to a new article, and a disambiguation page created. Rwxrwxrwx 11:11, 10 July 2007 (UTC)
thread_title: REALITY

message: "Contrary to previous HP RPN calculators, which had a fixed four-level stack, the stack used by RPL is only limited by available calculator RAM."
I have a 48gx and it is not stack limited.  A quick test gave me more than 50 items in the stack.  I assume it is limited only by memory.
I don't know if other RPN calculators are stack limited.
Ponjo (talk) 01:01, 12 July 2008 (UTC)
replies: text: Since the 48 is an RPL calculator, what is your point? My 41 has a four level stack. Thyl Engelhardt 213.70.217.172 (talk) 08:36, 10 December 2008 (UTC)
thread_title:  Four level stack? 

message: I just got a HP 50g yesterday, and this is my first 'advanced' calculator so I'm in heaven :) I think this article could discuss the actual features of rpl a bit more. If no one else does so, I'll add the stuff myself but I guess I should get a few months of experience first. 
Some questions I'd like answered are: How to make recursive function calls? Can the compiler/interpreter transform tail recursion into simple loops? Are the types ordered in some kind of hirarchy or is the type space flat? Can one add new types (e.g. 'quaternions') and have them work with e.g the '+' function? 
I'll find out soon enough, but as I said, the article could mention this.  —Preceding unsigned comment added by 188.126.207.212 (talk) 04:26, 14 September 2009 (UTC)
thread_title:  Recursive functions etc 

message: If this is basically usable aas a general purpose language who's main availability happens to be calculator programming (as it appears on cursory glance it might, or might mostly), I (just little old me) think such should be 1 of the most obviouse aspects of the article itself.  If not how far away is it from such, and in what way.  My bias is great, here.  I basically no nothing about computers, and thats the 1st thing I wanted to know and looked to the article to find.  Slarty2 (talk) 23:36, 5 January 2011 (UTC)
thread_title:  general purposeness 

message: It needs it (though it is mainly use case). Daemonicky (talk) 12:42, 31 August 2011 (UTC)
thread_title:  RPL syntax highlighting is missing 

message: [] is correct? Could somebody provide a source that guillemets (namely,  and ) have such syntactic meaning in this language? Incnis Mrsi (talk) 08:45, 19 July 2012 (UTC)
thread_title:  Change << to « by MatthewMastracci 

message: In Variants: the language is overblown. Serious crash? Who dies from it? It's just a calculator. Reset it and move on.
As far as System RPL only being available via external tools, this certainly does not apply to the 50g. The HP doc (Advanced User Guide) explains how to code in Sys RPL and even ARM assembly with onboard tools that come preloaded from the factory. I don't know how far back this goes, but I believe Sys RPL was available natively on the 48 series as well. Someone who knows definitely should fix this all at once.87.68.23.11 (talk) 08:02, 4 December 2013 (UTC)
thread_title:  Variants: wrong and overblown