RPL for the 6502 circa 1981

[Katie Wasserman]

I think that you need to consider "RPL" in context. That context being the available languages on the Commodore PET with 8K of RAM circa 1980 when RPL was created. BASIC was built-in and slow but fairly memory efficient because it tokenized all the keywords. It also provided a built-in screen editor for those tokens/keywords. RPL used the BASIC-tokens and editor which was a huge plus since zero-RAM was needed for this aspect of the language. Programs written in RPL on a PET typically ran 10 times faster than those in BASIC while using less space. Admittedly, readability suffered because of the use of sometimes cryptic BASIC keywords but it is wasn't horrible to use.

The comparison to Forth is somewhat hyperbolic and totally unnecessary as there were no versions of Forth available for an 8K Commodore PET back in 1980-81. Although you might have been able to squeeze in part of some 6502 version of Forth there would be little memory left for use programs.