[squeak-dev] The Trunk: Morphic-mt.1769.mczNicolas Cellier nicolas.cellier.aka.nice at gmail.comTue May 18 19:51:00 UTC 2021
Hi Marcel, yes, maybe with some ellipsis ahead "..." to denote the fact that it's infinite... Le mar. 18 mai 2021 à 16:13, Marcel Taeumel <marcel.taeumel at hpi.de> a écrit : > > Am 18.05.2021 15:55:23 schrieb Marcel Taeumel <marcel.taeumel at hpi.de>: > Hi Nicolas, > > > We could express this in inspectors with a bits field and a leading > ... 00000000 or ... 11111111 digit (yes digits are 1 byte long currently). > > You mean like this? > > DEC -2 > HEX -02 > OCT -002 > BIN -0010 > BIT 1111 1111 1111 1110 > ? > > Best, > Marcel > > Am 17.05.2021 18:53:42 schrieb Nicolas Cellier < > nicolas.cellier.aka.nice at gmail.com>: > Hi all, > Virtual Machine implementation is a detail. SmallInteger are two > complement, while LargeNegativeInteger are sign magnitude (with sign > encoded in the class). From bit perspective (bitAnd: bitOr: bitAt: etc...), > all Integer behave as two complement with an infinite sequence of 1 for > negative, and infinite sequence of 0 for positive. We could express this in > inspectors with a bits field and a leading ... 00000000 or ... 11111111 > digit (yes digits are 1 byte long currently). > > Le lun. 17 mai 2021 à 15:35, Marcel Taeumel <marcel.taeumel at hpi.de> a > écrit : > >> > The decimal representation is just one of many equivalent >> representations. >> >> The problem being that the basic (machine) representation is not clear. I >> think its 2's complement. HEX and OCT -- I suppose -- are very close to the >> machine representation. >> >> That's not an issue for positive numbers. :-) >> >> Best, >> Marcel >> >> Am 17.05.2021 14:00:36 schrieb Thiede, Christoph < >> christoph.thiede at student.hpi.uni-potsdam.de>: >> >> > > But this would not really match the actual object layout of integers >> in Squeak which can have arbitrary sizes ... >> > >> > So, the binary representation does not make sense, right? And neither >> does the HEX or OCT. :-) >> >> Why do you think so? The object layout of Squeak Integer is not something >> like "list of decimal digits". The decimal representation is just one of >> many equivalent representations. On the other hand, any complement semantic >> adds a completely new concept because it neglects the infinite size of >> integers. >> >> Best, >> Christoph >> >> ------------------------------ >> *Von:* Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org> im >> Auftrag von Taeumel, Marcel >> *Gesendet:* Montag, 17. Mai 2021 13:08:47 >> *An:* squeak-dev >> *Betreff:* Re: [squeak-dev] The Trunk: Morphic-mt.1769.mcz >> >> > But this would not really match the actual object layout of integers >> in Squeak which can have arbitrary sizes ... >> >> So, the binary representation does not make sense, right? And neither >> does the HEX or OCT. :-) >> >> Best, >> Marcel >> >> Am 17.05.2021 13:07:28 schrieb Thiede, Christoph < >> christoph.thiede at student.hpi.uni-potsdam.de>: >> >> > And I would have expected a 2's complement, right? >> >> >> Ah, now I see. :-) But this would not really match the actual object >> layout of integers in Squeak which can have arbitrary sizes ... >> >> >> In my opinion, we should just leave it as is (just maybe without the >> space), I don't really like such artificial limitations. :-) >> >> >> Best, >> >> Christoph >> ------------------------------ >> *Von:* Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org> im >> Auftrag von Taeumel, Marcel >> *Gesendet:* Montag, 17. Mai 2021 12:52:23 >> *An:* squeak-dev >> *Betreff:* Re: [squeak-dev] The Trunk: Morphic-mt.1769.mcz >> >> > Apart from that, I would have expected '-02' instead of '- 02'. :-) >> >> And I would have expected a 2's complement, right? Or even drop this >> representation for negative numbers altogether? >> >> Best, >> Marcel >> >> Am 17.05.2021 12:49:51 schrieb Thiede, Christoph < >> christoph.thiede at student.hpi.uni-potsdam.de>: >> >> Nice catch! :-) >> >> >> For anyone else wondering about this glitch: >> >> Before: >> >> >> After: >> >> >> IMO our printing protocol on Number should have a padded argument similar >> to the (post-comma) decimal places. >> Apart from that, I would have expected '-02' instead of '- 02'. :-) >> >> Best, >> Christoph >> ------------------------------ >> *Von:* Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org> im >> Auftrag von commits at source.squeak.org <commits at source.squeak.org> >> *Gesendet:* Donnerstag, 6. Mai 2021 19:05:29 >> *An:* squeak-dev at lists.squeakfoundation.org; >> packages at lists.squeakfoundation.org >> *Betreff:* [squeak-dev] The Trunk: Morphic-mt.1769.mcz >> >> Marcel Taeumel uploaded a new version of Morphic to project The Trunk: >> http://source.squeak.org/trunk/Morphic-mt.1769.mcz >> >> ==================== Summary ==================== >> >> Name: Morphic-mt.1769 >> Author: mt >> Time: 6 May 2021, 7:05:24.828981 pm >> UUID: 8109f744-f1f3-7048-8646-fed21a8e23d4 >> Ancestors: Morphic-ct.1768 >> >> Fixes minor glitch in objext explorers on integers. >> >> This makes me wonder ... what are the expectations for negative integers >> here? >> >> =============== Diff against Morphic-ct.1768 =============== >> >> Item was changed: >> ----- Method: Integer>>explorerContents (in category >> '*Morphic-Explorer') ----- >> explorerContents >> >> ^#( >> ('hexadecimal' 16 2) >> ('octal' 8 3) >> ('binary' 2 4)) collect: [ :each | | label group | >> group := each third. >> + label := self abs printStringBase: each second. >> - label := self printStringBase: each second. >> label := label padded: #left to: (label size >> roundUpTo: group) with: $0. >> label := String streamContents: [:s | >> + self negative ifTrue: [s nextPutAll: '- >> ']. >> (1 to: label size by: group) >> do: [:index | >> 1 to: group do: [:gIndex >> | >> s nextPut: >> (label at: index + gIndex - 1)]] >> separatedBy: [s space]]. >> >> ObjectExplorerWrapper >> with: label >> name: each first translated >> model: self ]! >> >> >> >> > -------------- next part -------------- An HTML attachment was scrubbed... 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