steve@siemens.UUCP (09/04/86)
Why do people choose Symbolics/ZetaLisp/CommonLisp over
Xerox Dandelion/Interlisp?
I have been "brought up" on Interlisp and had virtually no exposure to
Maclisp derivatives, but more to the point, I've been brought up on the
Xerox Dandelion lisp machine and never used a Symbolics. Every chance I
get, I try to find out what a Symbolics/Zetalisp machine has that the
Dandelion doesn't. So far I have found only the following:
1) More powerful machine (but less power per dollar).
2) The standard of Commonlisp (only the past couple years).
3) People are ignorant of what the Dandelion has to offer.
4) Edit/debug cycle (and editor) very similar to old standard systems
such as Unix/C/Emacs or TOPS/Pascal/Emacs, and therefore easier
for beginners with previous experience.
I have found a large number of what seem to be advantages of the Xerox
Dandelion Interlisp system over the Symbolics. I won't post anything
now because this already is too much like an ad for Xerox, but you might
get me to post some separately.
I am not personally affiliated with Xerox (although other parts of my
company are). I am posting this because I am genuinely curious to find
out what I am missing, if anything.
By the way, the Interlisp system on the Dandelion is about 5 megabytes
(it varies depending on how much extra stuff you load in - I've never
seen the system get as large as 6 Mb). I hear that Zetalisp is 24 Mb.
Is that true? What is in it, that takes so much space?
Steven J. Clark, Siemens Research and Technology Laboratory etc.
{ihnp4!princeton | topaz}!siemens!steve
something like this ought to work from ARPANET: steve@siemens@spice.cs.cmu
(i.e. some machines at CMU know siemens).royt@gatech.CSNET (Roy M Turner) (09/05/86)
In article <25800003@siemens.UUCP> steve@siemens.UUCP writes: > . . . >Every chance I >get, I try to find out what a Symbolics/Zetalisp machine has that the >Dandelion doesn't. So far I have found only the following: > >1) More powerful machine (but less power per dollar). > >2) The standard of Commonlisp (only the past couple years). > >3) People are ignorant of what the Dandelion has to offer. > >4) Edit/debug cycle (and editor) very similar to old standard systems > such as Unix/C/Emacs or TOPS/Pascal/Emacs, and therefore easier > for beginners with previous experience. . . . > >By the way, the Interlisp system on the Dandelion is about 5 megabytes >(it varies depending on how much extra stuff you load in - I've never >seen the system get as large as 6 Mb). I hear that Zetalisp is 24 Mb. >Is that true? What is in it, that takes so much space? > >Steven J. Clark, Siemens Research and Technology Laboratory etc. >{ihnp4!princeton | topaz}!siemens!steve > As a user of Symbolics Lisp machines, I will try to answer some of Steve's comments. We have had Symbolics machines here since before I started on my degree two years ago; we recently were given thirteen Dandelions and two DandyTigers by Xerox. We use the Symbolics as our research machines, and the Xerox machines for teaching AI. The Symbolics are more powerful, as Steve says, and quite possibly he is right about the power per dollar being less for them than for Xerox; since the Xerox machines were free to us, certainly he's right in our case! :-) However, I find the Dandelions abysmally slow for even small Lisp programs, on the order of the ones we use in teaching (GPS (baby version), micro versions of SAM, ELI, etc.). To contemplate using them for the very large programs that we develop as our research would be absurd--in my opinion, of course. The "standard" of CommonLisp will (so Xerox tells us) be available for the Dandelions soon...'course, they've been saying that for some time now :-). So the two machines may potentially be equal on that basis. ZetaLisp is quite close to CommonLisp (since it was one of the dialects Common Lisp is based on), and also close to other major dialects of lisp--Maclisp, etc.--enough so that I've never had any trouble switching between it and other lisps...with one exception--you guessed it, Interlisp-D. I realize that whatever you are used to colors your thinking, but Lord, that lisp seems weird to me! I mean, comments that return values?? Gimme a break! "People are ignorant of what the Dandelion has to offer." I agree. I'm one of the people. It has nice windows, much less complicated than Symbolics. MasterScope is nice, too. So is the structure editor, but that is not too much of a problem to write on any other lisp machine, and is somewhat confusing to learn (at least, that's the attitude I perceive in the students). What the Dandelions *lack*, however, is any decent file manipulation facilities (perhaps Common Lisp will fix this), a nice way of handling processes, a communications package that works (IP-TCP, at least the copy we received, will trash the hard disk when our UNIX machines write to the DandyTigers...the only thing that works even marginally well is when we send files from the Symbolics! Also, the translation portion of the communication package leaves extraneous line-feeds, etc., lying about in the received file), and A DECENT EDITOR! Which brings us to the next point made by Steve: >4) Edit/debug cycle (and editor) very similar to old standard systems > such as Unix/C/Emacs or TOPS/Pascal/Emacs, and therefore easier > for beginners with previous experience. This is true. However, it is also easier for experts and semi-experts (like me) who may or may not have had prior experience with EMACS. The Dandelions offer a structure editor (and Tedit for text, but that doesn't count) and that's it...if you want to edit something, you do it function by function. Typically, what I do and what other people do on the Xerox machines is enter a function in the lisp window, which makes it very difficult to keep track of what you are doing in the function, and makes it mandatory that you enter one function at a time. Also, the function is immediately evaluated (the defineq is, that is) and becomes part of your environment. Heaven help you if you didn't really mean to do it! At least with ZMACS you can look over a file before evaluating it. Another gripe. Many of our programs used property lists, laboriously entered via the lisp interactor. We do a makefile, and voila--next time we load the file, the properties aren't there! This has yet to happen when something is put in an edit buffer and saved to disk on the Symbolics. Perhaps there is a way of editing on the Xerox machines that lends itself to editing files (and multiple files at once), so that large programs can be entered, edited, and documented (Interlisp-D comments are rather bad for actually documenting code) easily...if so, I haven't found it. Another point in Symbolics favor: reliability. Granted, it sometimes isn't that great for Symbolics, either, but we have had numerous, *numerous* software and hardware failures on the Dandelions. It's so bad that we have to make sure the students save their functions to disk often, and have even had to teach them how to copy sysouts and handle dead machines, since the machines lock up from time to time with no apparent cause. And the students must be cautioned not to save their stuff only to one place, but to save it to the file server, a floppy, and anywhere else they can, since floppies are trashed quite often. Dribble to the hard disk, forget to turn dribble off, there goes the hard disk... Type (logout t) on the Dandelions to cause it not to save your world, and there goes the Dandelion (it works on the DandyTigers). About worlds and sysouts. The Symbolics has a 24-30 meg world, something like that. This is *not* just lisp--it is your virtual memory, just as it is in a Xerox Sysout. The difference in size reflects the amount of space you have at your disposal when creating conses, not the relative sizes of system software (though I imagine ZetaLisp is larger than Interlisp-D). You do not necessarily save a world each time you logout from a Symbolics; you do on a Dandelion...thus the next user who reboots a Symbolics gets a clean lisp, whereas the next user of a Dandelion gets what was there before unless he first copies another sysout and boots off of it. It is, however, much harder to save a world on the Symbolics than on the Xerox machines. Well, I suppose I have sounded like a salesman for Symbolics. I do not mean to imply that Symbolics machines are without faults, nor do I mean to say that Xerox machines are without merit! We are quite grateful for the gift of the Xerox machines; they are useful for teaching. I just tried to present the opinions of one Symbolics-jaded lisp machine user. Back to the Symbolics machine now...I suppose that the DandyTiger beside it will bite me! :-) Roy
mkent@violet.berkeley.edu (09/07/86)
As a long-term user of Interlisp-D, I'd be very interested in hearing an *informed* comparison of it with ZetaLisp. However, I'm not particularly interested in hearing what an experienced Zetalisp user with a couple of hours of Interlisp experience has to say on the topic, other than in regard to issues of transfer and learnability. I spent about 4 days using the Symbolics, and my initial reaction was that the user interface was out of the stone age. But I realize this has more to do with *my* background then with Zetalisp itself. Is there anyone out there with *non-trivial* experience with *both* environments who can shed some light on the subject? Marty Kent "You must perfect the Napoleon before they finish Beef Wellington! The future of Europe hangs in the balance..."
hogge@uiucdcsp.CS.UIUC.EDU (09/09/86)
>...I spent about 4 days using >the Symbolics, and my initial reaction was that the user interface was out >of the stone age. But I realize this has more to do with *my* background >then with Zetalisp itself. Four days *might* be enough time to get familiarize yourself with the help mechanisms, if that's specifically what you were concentrating on doing. Once you learn the help mechanisms (which aren't bundled all that nicely and are rarely visible on the screen), your opinion of the user interface will grow monotonically with use. If you are interested in having more visible help mechanisms for first-time users, check out what the TI Explorer adds to the traditional Zetalisp environment. LMI and Sperry also provide their own versions of the environment. --John
mob@mit-amt.MIT.EDU (Mario O. Bourgoin) (09/10/86)
In article <3500016@uiucdcsp>, hogge@uiucdcsp.CS.UIUC.EDU writes: > >...I spent about 4 days using > >the Symbolics, and my initial reaction was that the user interface was out > >of the stone age..... > > Four days *might* be enough time to get familiarize yourself with the help > mechanisms, if that's specifically what you were concentrating on doing. Four days to learn the help mechanisms? Come on, an acceptable user interface should give you control of help within minutes _not days_. Seriously folks, it took me less than 10 seconds to learn about ZMACS's apropos on the old CADRs and before the end of the day, I knew about a lot more. Have you ever used the "help" key? The Symbolics's software isn't much different from the CADR's. I'll grant that the lispm's presentation of information isn't that obvious or elegant but it isn't stone age and doesn't require 4 days to get a handle on. If you're arguing internals, I haven't worked with the Dandelion so I can't provide an opinion on it. The CADR's user interface software was certainly featureful and appeared to my eyes to come from a different school than what I later saw of Xerox's software. It is useful and manipulable but didn't look intended to be programmed by anyone just off the street. If you want to learn the internals of the user interface, _then_ i'll grant you four days (and more). --Mario O. Bourgoin
royt@gatech.CSNET (Roy M Turner) (09/11/86)
In response to a prior posting by me, Marty (mkent@violet.berkely.edu) writes: > > As a long-term user of Interlisp-D, I'd be very interested in hearing an >*informed* comparison of it with ZetaLisp. However, I'm not particularly >interested in hearing what an experienced Zetalisp user with a couple of >hours of Interlisp experience has to say on the topic... > ... Who, me? :-) If I was unclear in my posting, I apologize. I have had a bit more than two hours of experience w/ Dandelions. I used them in a class I was taking, and also was partly responsible for helping new users and for maintaining some of the software on them. Altogether about 4 months of fairly constant use. Another posting said we were using outdated software; that is undoubtedly correct, as we just got Coda; we were using Intermezzo. Some problems are probably fixed. However, we have not received the new ip-tcp from Xerox...but, what do you expect with free machines? :-) Roy ------ Above opionions my own...'course, they *should* be everyone's! :-) -- Roy Turner School of Information and Computer Science Georgia Insitute of Technology, Atlanta Georgia, 30332 ...!{akgua,allegra,amd,hplabs,ihnp4,seismo,ut-ngp}!gatech!royt
hogge@uiucdcsp.CS.UIUC.EDU (09/12/86)
>> Four days *might* be enough time to get familiarize yourself with the help >> mechanisms, if that's specifically what you were concentrating on doing. > >Four days to learn the help mechanisms? Come on, an acceptable user >interface should give you control of help within minutes _not days_. >Seriously folks, it took me less than 10 seconds to learn about >ZMACS's apropos on the old CADRs and before the end of the day, I knew >about a lot more. Have you ever used the "help" key? >software isn't much different from the CADR's. I'll grant that the >lispm's presentation of information isn't that obvious or elegant but >it isn't stone age and doesn't require 4 days to get a handle on. There's more subtle help available on the machine than just the help key, and my experience is that it takes a long time for one to learn the mechanisms that are there. The HELP key *is* the main source of help, but not the only source. Examples include: 1. use of Zmacs meta-point to find examples of how to do things (such as hack windows) from the system source, 2. use of c-/ in the Zmacs minibuffer for listing command completions (and what a drag if you don't know about this command) 3. the importance of reading who-line documentation 4. use of the Apropos function to hunt down useful functions, as well as WHO-CALLS 5. use of the various Lisp Machine manufacturer's custom help mechanisms, such as the Symbolics flavor examiner and documentation examiner, or TI's Lisp-completion input editor commands and Suggestions Menus. The Lisp Machine is a big system, and there's lots of good help available. But it isn't trivial learning how to get it nor when to seek it. --John
sbc@wucs.UUCP (Steve Cousins) (09/12/86)
In article <322@mit-amt.MIT.EDU> mob@mit-amt.UUCP writes: >... It is useful and >manipulable but didn't look intended to be programmed by anyone just >off the street. If you want to learn the internals of the user >interface, _then_ i'll grant you four days (and more). > >--Mario O. Bourgoin I think you could argue that *no* machine (AI or otherwise) can be programmed by anyone just off the street :-). I haven't used the Symbolics, but my view of the Dandelion has changed drastically since taking a course on it by Xerox. The interface is very powerful and well-integrated, but the "infant mortality curve" (the time to get good enough not to crash the machines) is somewhat high. [Disclaimer: These machines are supposed to be much better when networked than stand-alone. My changein attitude occurred just as we got ours on the network, and I'm not sure how much to attribute to the class, and how much to attribute to the network]. I like the Dandelion now, but the first 4 days did not give me a good impression of the machine. There is a lot to say about learning a new machine from a guru... Steve Cousins ...ihnp4!wucs!sbc or sbc@wucs.UUCP Washington University
WDMCU@CUNYVM.BITNET (09/12/86)
In article <3500016@uiucdcsp>, hogge@uiucdcsp.CS.UIUC.EDU says: >Once you learn the help mechanisms (which aren't bundled all that nicely and >are rarely visible on the screen), your opinion of the user interface will >grow monotonically with use. If you are interested in having more visible ^^^^^^^^^^^^^ Could you please define this word in this context. Thanks. (This is a serious question) /*--------------------------------------------------------------------*/ /* Bill Michtom - work: (212) 903-3685 home: (718) 788-5946 */ /* */ /* WDMCU@CUNYVM (Bitnet) Timelessness is transient */ /* BILL@BITNIC (Bitnet) */ /* */ /* Never blame on malice that which can be adequately */ /* explained by stupidity. */ /* A conclusion is the place where you got tired of thinking. */ /*--------------------------------------------------------------------*/