wmb@MITCH.ENG.SUN.COM (Mitch Bradley) (02/11/91)
> >SET-ORDER can be done portably in ANS FORTH > > Only if everyone implements *ALL* the extension word sets. In our own > case, I can definitely promise you that LMI will *NOT* implement the > extension words that it considers brain-damaged, which definitely > includes ALSO and ONLY. GET/SET-ORDER was invented in order to resolve the conflict between the proponents of run-time search order specification and those who consider ALSO/ONLY to be brain-damaged. (ALSO/ONLY indeed has some serious technical flaws; nevertheless, it is useful.) I believe that the design of GET/SET-ORDER addresses the problems with ALSO/ONLY, while being simpler than ALSO/ONLY. Indeed, GET/SET-ORDER was originally proposed as a "fix" for the most fundamental flaw of ALSO/ONLY. Then I realized that it is sufficiently powerful that ALSO/ONLY can be easily implemented in terms of GET/SET-ORDER. John Hayes and I have figured out how to implement a few other popular search order schemes in terms of GET/SET-ORDER. From what Martin Tracy has told me of LMI's search order mechanism, I believe it can be expressed in terms of GET/SET-ORDER as well. The SEARCH ORDER "base" wordset now contains GET/SET-ORDER and a few related words (GET/SET-CURRENT , WORDLIST, and FORTH-WORDLIST). ALSO/ONLY has been banished to the SEARCH ORDER EXTENSION wordset. I would be interested to learn of other wordsets that LMI considers to be brain-damaged, and why. (Don't bother mentioning the strings wordset; everybody in the world seems to have different and mutually-incompatible ideas about what should be in that particular wordset, so I expect that it will remain brain-damaged). Mitch