Squeak-dev July 1999

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139 participants
367 discussions

Re: unused message
by JArchibald＠aol.com 02 Jul '99

02 Jul '99

On 7/2/99 4:36:35 PM EDT, mtidwell(a)mail.com writes: << is it possible to turn off the "blah appears to be unused in this method. OK to remove it?" prompt? in a particular method i have defined a temporary and it is used, but every time i save changes, i get this message. >> What is the text of the message which is giving you trouble? Jerry.

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Re: [BUG?] Swiki bug, and some questions
by Lex Spoon 02 Jul '99

02 Jul '99

No idea on the dropped connections. Could you try it on a different OS and see if it still happens? Also, you could check that your VM is the newest available for your platform. Regarding line endings, Swikis actually do translate them. Internally, Swikis use squeak-friendly CR terminators. On the network, Swikis use CRLF terminators on output, and allow for all three common conventions on input. They use the rather long-named #withSqueakLineEndings and #withInternetLineEndings methods to handle the translations. Perhaps the extra lines you are seeing are because the regular Swiki formatter adds a <br> to the end of each line? If so, you could try using the LessHTMLFormatter instead of the regular formatter. The regular formatter is nice if you enter a lot of code or email messages, but in some cases it is friendlier than you like. Lex Chris Cunningham <chrisc(a)wolfenet.com> wrote: > A question about Swikis - If I try to paste in text that I don't want > formatted, it appears that I need to use the HTML <pre></pre> tags. Doing > this, I get a blank line between each line of displayed text. I suspect > that this could be called a bug as well. Maybe when the Swiki takes in > text, it needs to convert end of line characters into a generic format. Of > course, it can't do this based on the platform that is running the Swiki, > since the person creating the page can be on any platform. > > Thanks

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Re: [ENH] OS-level events
by Lex Spoon 02 Jul '99

02 Jul '99

Marcel Weiher <marcel(a)system.de> wrote: > > From: "Lex Spoon" <lex(a)cc.gatech.edu> > > In Morphic, they're actually already gone. That's why you can > scroll a text pane > > and have your BouncingAtomsMorph keep bouncing around while you do > it. Of > > course, the logic for menus and for text highlighting and things > like that, which > > take a long time to execute, are made more complicated because > they have to store > > intermediate states in instance variables--the extra interactivity > is not for > > free. > > Wouldn't that added complexity go away if an asynchronous > message/event delivery model were used so that these tasks could be > coded as plain methods that wait for messages to arrive? > If I understand what you mean, they are actually already coded that way: Morphic is based on events, it's just that it normally creates its events by polling the mouse state instead of waiting for OS events to arrive. Morphs deal with input by implementing methods like mouseDown: and keyStroke:. The main problem is that when an event happens, a new method has to run from scratch. Thus event handlers can't just pause in the middle of a loop and wait for the next event, because the loop has to exit before it can get the next event. Event-based analoguse to control loops end up simulating the loops in the original control loop, but without the convenience of the language-provided looping constructs. Further problems with the events approach are that the events might come in any order (unlike the case of MVC where you can just ask for only the kinds of input you are currently interested in), and that the outside world might change between two events (wherease in MVC, no code runs except your own, until you exit the loop). To give a specific example, consider text highlighting code. In MVC there is a loop something like this: [ Sensor redButtonPressed ] whileTrue: [ "...update the highlight..." ] The Morphic text highlighter, on the other hand, must hook mouseDown: to start highlighting and store the fact that a highlight is in progress, and mouseMove: to extend the highlight. mouseMove: does the work in the body of the above whileTrue: loop, except that mouseMove: must also check each time it starts up that there is indeed a highlight in progress. Furthermore, you have to be careful that the selection-updating code, doesn't interfere with the text-updating code (I just checked, and in fact Morphic isn't as smooth as it could be if you hold down the mouse button doing a highlight and then type a few keys.) Of course, the event-handling paradigm fits Morphics goals extremely well. The question is how to deal with its effects? Maybe continuations would help. An event handler *could* be allowed to stop at any arbitrary point to wait for another event. (This could be implemented using suspended Processes). It would certainly make the event handlers simpler, because they could go back to using regular old loops. But then, how do you arrange for the suspended handlers to be given the events they need? And how do you keep from having all these suspended handlers around that might never in fact get woken back up (eg, their window closed)? Has anyone here ever worked in such a system? (And, is Squeak bound to touch on every single OS and programming language issue that has come up in the last 20+ years, as it goes along? :)) Lex

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[BUG?] Swiki bug, and some questions
by Chris Cunningham 02 Jul '99

02 Jul '99

I have a Swiki setup at work, and created a page with about a dozen tables on it. The page was about 14K worth of data. The Swiki took this this page fine, and showed it fine, but any time that I tried to edit it later, it brought up about half of the source, and then informed me that the connection to the server was broken. I eventually fixed the page (by editing the file with an outside editor), but I'm wondering what the limit of for a Swiki page is that you can edit. The Swiki is running in Squeak 2.4c (plain), on NT. I was attempting to edit it with IE5. A question about Swikis - If I try to paste in text that I don't want formatted, it appears that I need to use the HTML <pre></pre> tags. Doing this, I get a blank line between each line of displayed text. I suspect that this could be called a bug as well. Maybe when the Swiki takes in text, it needs to convert end of line characters into a generic format. Of course, it can't do this based on the platform that is running the Swiki, since the person creating the page can be on any platform. Thanks

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Re: AI, intelligent agents and nonesuch
by Jerome.Garcia＠wj.com 02 Jul '99

02 Jul '99

Hi Warner, You might also want to check out http://www.starbridgesystems.com/home/index.htm for related info about their reconfigurable computer systems. In their SBS TECHNOLOGY BREAKTHROUGHS page in their TECHNOLOGY section they mutter about advanced artificial intelligence algorithms and techniques such as recursion, cellular autonoma, heuristics and genetic algorithms and the system evolving itself. It all sounds very impressive but to me somewhat incomprehensible. Need more data. I don't know whether it is all hype but I intend to learn more. Jerome ______________________________ Reply Separator _________________________________ Subject: AI, intelligent agents and nonesuch Author: Warner Onstine <warner(a)eblox.com> at INTERNET Date: 7/2/99 5:37 PM Hi all, I heard about this from a friend of mine, whom is also on the mailing list (Lawson English), and he mentioned that there was some discussion going on about creating AI or intelligent OS using Squeak. This intrigued quite a bit, as this is a long-term project that I have been thinking about undertaking over the next (who knows how many years). Here were my thoughts on the subject: 1. There is a project called Tierra which created an a-life organism that actually modifies its own source - the creator started with an 80-byte program which then modified itself down to 21 bytes. The closest a human (one who was quite adept at assembler I might add) could get was 30-bytes. That is a tremendous improvement. 2. By using intelligent agents as the base OS we then begin to see the benefits of it actually learning and improving itself for any given user. Of course some things would need to be constant so that others could use it in an impersonal mode, but you get the idea. 3. If we integrate the idea of a self-improving OS we could over time actually see an OS that actually evolves and learns not only from the User but also from the Net and other Users that it is connected to. I desperately would like to get in contact with anyone who has touched on these ideas or others that might be related. My initial thought was to get a cheap PowerPC and drop Linux-PPC on it and go from there seeing what could be done. Rant complete. -warner onstine

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AI, intelligent agents and nonesuch
by Warner Onstine 02 Jul '99

02 Jul '99

Hi all, I heard about this from a friend of mine, whom is also on the mailing list (Lawson English), and he mentioned that there was some discussion going on about creating AI or intelligent OS using Squeak. This intrigued quite a bit, as this is a long-term project that I have been thinking about undertaking over the next (who knows how many years). Here were my thoughts on the subject: 1. There is a project called Tierra which created an a-life organism that actually modifies its own source - the creator started with an 80-byte program which then modified itself down to 21 bytes. The closest a human (one who was quite adept at assembler I might add) could get was 30-bytes. That is a tremendous improvement. 2. By using intelligent agents as the base OS we then begin to see the benefits of it actually learning and improving itself for any given user. Of course some things would need to be constant so that others could use it in an impersonal mode, but you get the idea. 3. If we integrate the idea of a self-improving OS we could over time actually see an OS that actually evolves and learns not only from the User but also from the Net and other Users that it is connected to. I desperately would like to get in contact with anyone who has touched on these ideas or others that might be related. My initial thought was to get a cheap PowerPC and drop Linux-PPC on it and go from there seeing what could be done. Rant complete. -warner onstine

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swiki down again
by Bob Arning 02 Jul '99

02 Jul '99

I just tried to access the swiki and got simply: Message not understood: last Cheers, Bob

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RE: comparing Sequenceable Collections.
by Jarvis, Robert P. 02 Jul '99

02 Jul '99

(My initial reply to Peter's note went directly to him instead of to the list, so I'm redirecting this so as to get everyone involved). I was rather surprised to find that #= was used when removing elements from a collection. I'm guessing that the culprit is #OrderedCollection>>remove:ifAbsent, which currently looks like remove: oldObject ifAbsent: absentBlock | index | index _ firstIndex. [index <= lastIndex] whileTrue: [oldObject = (array at: index) ifTrue: [self removeIndex: index. ^ oldObject] ifFalse: [index _ index + 1]]. ^ absentBlock value It looked to me like the #= send in the sixth line could be replaced by #== without compromising the intent of the method, but after a bit of experimenting I found this wasn't a good idea. Consider if you're storing strings in a collection: | col | col := OrderedCollection new. 1 to: 10 do: [ :i | col add: i printString ]. Transcript show: col printString. OK, now we've got strings '1' '2'...'10' stored in the collection. If you replace the #= in OrderedCollection>>remove:ifAbsent: with #== and accept the change, then try the following col remove: '1' ifAbsent: [ Transcript show: 'Couldn''t find it' ] you get the message Couldn't find it displayed on the Transcript. This is because different strings with the same contents are not the identical object, so the comparison in question fails and the object is never removed from the collection. So it looks like the proper way to compare objects in OrderedCollection>>remove:ifAbsent: is with the #= message, if you're planning on storing non-identity objects in it. Maybe you could subclass OrderedCollection to get the behavior you want, e.g. create a DictionaryCollection class which reimplements remove:ifAbsent using #== instead of #= as the comparison method. This may be something of a heavyweight solution, and is perhaps more trouble than it's worth, so your solution of generating a new collection may be your best option. Also, you might consider rewriting your fragment as collection := collection reject: [ :each | each == aDictionary ] as it seems to be a bit clearer about what's going on. Bob Jarvis The Timken Company > -----Original Message----- > From: Peter Novak [SMTP:pno@whitestein.com] > Sent: Friday, July 02, 1999 9:04 AM > To: Jarvis, Robert P. > Subject: Re: comparing Sequenceable Collections. > > Hi. Now it's okay, but it seems to me not very practical to use > solution like is mine. > > I had few OrderedCollections and it's elements were big Dictionaries > (like Smalltalk). I tought that the easiest way to to remove some element > from > those OrderedCollections is > > colection remove: aDictionary ifAbsent: [Object inform: 'nothing']. > > but when the thing I wanted to remove was Smalltalk Dictionary it took > the Squeak too much time (because of using message = somwhere deeper in > the > system). So I think that in todays state it's impossible (in > normal time) to remove large dicionaries (or large collections) from > another large collections. My solution was: > > collection := (collection select: [:each | (each == aDictionary) not]. > > but it seems to me little bit unpractical. > > nowo. > > p.s. > I'm a Squeak newbie and after I saw that thing are really practical in > Squeak, > such abnormality can suprise me a lot. ;>>> > > > > -----Original Message----- > From: Jarvis, Robert P. <Jarvisb(a)timken.com> > To: 'Peter Novak' <pno(a)whitestein.com> > Date: 2. jl 1999 13:05 > Subject: RE: comparing Sequenceable Collections. > > > >Do you need to compare all the values, or just make sure they're the same > >object? If the latter, try > > > > Smalltalk == Smalltalk > > > >Bob Jarvis > >The Timken Company > > > >> -----Original Message----- > >> From: Peter Novak [SMTP:pno@whitestein.com] > >> Sent: Friday, July 02, 1999 6:38 AM > >> To: squeak > >> Subject: comparing Sequenceable Collections. > >> > >> Hi, > >> I have problem with comparing SequenceableCollections. I needed to > >> evaluate > >> something like > >> Smalltalk = Smalltalk. > >> After I tried to evaluate it, I waited for 2 minutes and it did > nothing. > >> It's too slow for > >> normal using. Isn't it bad? > >> > >> peter. > >> > >> << File: Peter Novak.vcf >> > > << File: Peter Novak.vcf >>

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comparing Sequenceable Collections.
by Peter Novak 02 Jul '99

02 Jul '99

Hi, I have problem with comparing SequenceableCollections. I needed to evaluate something like Smalltalk = Smalltalk. After I tried to evaluate it, I waited for 2 minutes and it did nothing. It's too slow for normal using. Isn't it bad? peter. Attachment converted: Anon:Peter Novak.vcf (TEXT/R*ch) (0000AD6D)

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RE: Is sqeak 2.3 beta ready for Y2K?
by Duane T Williams 02 Jul '99

02 Jul '99

>...and Y3K, Y4K, Y5K, etc... > >Date today addDays: 400 -> "4 August 2000" >Date today addDays: 4000 -> "13 June 2010" >Date today addDays: 40000 -> "5 January 2109" >Date today addDays: 400000 -> "29 August 3094" Stephen: Did you check that all those dates are correct? The next step in the iteration yields my birthday! :) Date today addDays: 4000000 -> 15 February 12951 -Duane

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