March 2018 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Bitwise operations in ByteArray (slicing, etc.)

by Esteban A. Maringolo

I do bitshifts and masks on Integer. What if you want to take the bits from the 3rd to the 7th? You have to do a some arithmetic to get the slice you want. I'm simply asking for something more dev-friendlier that adds a "layer" on top of that, but that internally does regular bitwise. What I don't like about Integers is that you "lose" information about the zero bits to the left, and with a ByteArray you don't, because the array is fixed size. E.g. (1 << 16) printStringBase: 16. "'10000'" #[1 0 0] hex "'010000'" Maybe I'm too lazy asking when I could have done it myself :) Regards, Esteban A. Maringolo 2018-03-04 16:40 GMT-03:00 Sven Van Caekenberghe <sven(a)stfx.eu>: > Take a 24-bit number and you want to isolate the first 5 (these are actually the last, higher order) bits. > > n := 2r101010001111000011110000. > n >> (16+3). > > If necessary, you can apply a mask (assume there are bits earlier/later still). > > (n >> (16+3)) bitAnd: 2r11111 > > Large integers behave as bit strings, see the 'bit manipulation' protocol, and are efficient at it. > >> On 4 Mar 2018, at 20:29, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: >> >> Is there any package/library that makes bitwise operations as simple >> as with an Integer, but for larger numbers (as in a ByteArray). >> >> Something that allows me to "slice" a sequence of bits, or extract >> some using the same protocol as with a String of ones and zeros. >> >> Now when I need to work with sequence of bits, I convert an Integer to >> a zero padded version of it up a known size, and then do #copyFrom:to: >> to extract what I need and read back the number from it. >> >> I could use a bytearray for it, but as its name implies, it is >> oriented towards bytes rather than bits (as in the case of Integer). >> >> Now I do stuff like the following to to extract the first 5 bits of a >> fixed length 256 bit array (an Integer). >> >> Integer >> readFrom: >> (((SHA256 hashMessage: message)) asInteger >> printStringBase: 2 length: 256 padded: true) >> copyFrom: 1 to: 5) >> base: 2 >> >> I understand bitwise operations, but I couldn't find something that >> does the above in a conciser way. >> >> Performance in my case isn't critical, but working with strings is >> probably two orders of magnitude slower than manipulating bits in >> integers or ByteArrays >> >> Regards, >> >> Esteban A. Maringolo >> > >

March 4, 2018

Re: [Pharo-users] Bitwise operations in ByteArray (slicing, etc.)

by Sven Van Caekenberghe

Take a 24-bit number and you want to isolate the first 5 (these are actually the last, higher order) bits. n := 2r101010001111000011110000. n >> (16+3). If necessary, you can apply a mask (assume there are bits earlier/later still). (n >> (16+3)) bitAnd: 2r11111 Large integers behave as bit strings, see the 'bit manipulation' protocol, and are efficient at it. > On 4 Mar 2018, at 20:29, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: > > Is there any package/library that makes bitwise operations as simple > as with an Integer, but for larger numbers (as in a ByteArray). > > Something that allows me to "slice" a sequence of bits, or extract > some using the same protocol as with a String of ones and zeros. > > Now when I need to work with sequence of bits, I convert an Integer to > a zero padded version of it up a known size, and then do #copyFrom:to: > to extract what I need and read back the number from it. > > I could use a bytearray for it, but as its name implies, it is > oriented towards bytes rather than bits (as in the case of Integer). > > Now I do stuff like the following to to extract the first 5 bits of a > fixed length 256 bit array (an Integer). > > Integer > readFrom: > (((SHA256 hashMessage: message)) asInteger > printStringBase: 2 length: 256 padded: true) > copyFrom: 1 to: 5) > base: 2 > > I understand bitwise operations, but I couldn't find something that > does the above in a conciser way. > > Performance in my case isn't critical, but working with strings is > probably two orders of magnitude slower than manipulating bits in > integers or ByteArrays > > Regards, > > Esteban A. Maringolo >

March 4, 2018

Bitwise operations in ByteArray (slicing, etc.)

by Esteban A. Maringolo

Is there any package/library that makes bitwise operations as simple as with an Integer, but for larger numbers (as in a ByteArray). Something that allows me to "slice" a sequence of bits, or extract some using the same protocol as with a String of ones and zeros. Now when I need to work with sequence of bits, I convert an Integer to a zero padded version of it up a known size, and then do #copyFrom:to: to extract what I need and read back the number from it. I could use a bytearray for it, but as its name implies, it is oriented towards bytes rather than bits (as in the case of Integer). Now I do stuff like the following to to extract the first 5 bits of a fixed length 256 bit array (an Integer). Integer readFrom: (((SHA256 hashMessage: message)) asInteger printStringBase: 2 length: 256 padded: true) copyFrom: 1 to: 5) base: 2 I understand bitwise operations, but I couldn't find something that does the above in a conciser way. Performance in my case isn't critical, but working with strings is probably two orders of magnitude slower than manipulating bits in integers or ByteArrays Regards, Esteban A. Maringolo

March 4, 2018

Re: [Pharo-users] HMAC-SHA512

by Esteban A. Maringolo

2018-03-04 0:45 GMT-03:00 Pierce Ng <pierce(a)samadhiweb.com>: > On Fri, Mar 02, 2018 at 11:24:36AM -0300, Esteban A. Maringolo wrote: >> There is a PBKDF2 package made by Udo Schneider, and seems to be >> easily pluggable with a different hashing algorithm, so I'd need a >> SHA512 class. > > OpenSSL-Pharo wraps the SHA512 in libcrypto. See LcEvpSHA512Test. > > https://github.com/PierceNg/OpenSSL-Pharo Thank you Pierce, I managed to make play the SHA classes of your OpenSSL wrapper with the PBKDF2 from Udo's plus HMAC from the Cryptography package. I sent you a pull-request <https://github.com/PierceNg/OpenSSL-Pharo/pull/1> that includes missing accessors that I needed to achieve the above interplay. The end result is this: https://github.com/eMaringolo/pharo-bip39mnemonic What I'm missing is a better PRNG to generate random numbers from 128 to 256 bits. But my main objective was a proof of concept that ended up being successful. Thanks for your help. Esteban A. Maringolo

March 4, 2018

Re: [Pharo-users] Yet another Pharo in docker

by Sean P. DeNigris

Sean P. DeNigris wrote >> https://hub.docker.com/r/herbysk/pharo/ > How are the images built from https://lolg.it/herby/pharo-docker? Researching a bit it seems that Docker Hub only supports GitHub and BitBucket, and IIUC you can't change the image name if you use automated building. Therefore, I assume you're going something custom. Is it manual? Or is there a way to set up triggers for a custom solution? Thanks. ----- Cheers, Sean -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

March 4, 2018

Re: [Pharo-users] [Pharo-dev] Looking for names for the booklet collection

by Peter UhnÃ¡k

> Pharo Tools & Technologies > Pharo Language & Environment +1 ... simple, obvious, to the point please no cryptic/"clever" names On Sun, Mar 4, 2018 at 4:41 PM, Benoit St-Jean via Pharo-users < pharo-users(a)lists.pharo.org> wrote: > > > ---------- Forwarded message ---------- > From: Benoit St-Jean <bstjean(a)yahoo.com> > To: Pharo Development List <pharo-dev(a)lists.pharo.org>, Ben Coman < > btc(a)openinworld.com> > Cc: Any question about pharo is welcome <pharo-users(a)lists.pharo.org> > Bcc: > Date: Sun, 4 Mar 2018 15:41:10 +0000 (UTC) > Subject: Re: [Pharo-dev] Looking for names for the booklet collection > Why not simply: > > Pharo Tools & Technologies > Pharo Language & Environment > > ----------------- > BenoÃ®t St-Jean > Yahoo! Messenger: bstjean > Twitter: @BenLeChialeux > Pinterest: benoitstjean > Instagram: Chef_Benito > IRC: lamneth > Blogue: endormitoire.wordpress.com > "A standpoint is an intellectual horizon of radius zero". (A. Einstein) > > > On Sunday, March 4, 2018, 10:30:46 AM EST, Ben Coman <btc(a)openinworld.com> > wrote: > > > > > On 4 March 2018 at 20:21, Stephane Ducasse <stepharo.self(a)gmail.com> > wrote: > > Hi > > I would like to make a distinction between booklet on Pharo > technologies (Smacc, Voyage, Scraping ...) and the booklets more > oriented towards teaching something with pharo (building an > interpreter, a reflective language...) > > > Pharo Applications / Inside Pharo > > Over Pharo / Under Pharo > > > Right now we have The Pharo Booklet Collection. > And I'm looking for two names > > the Pharo academic booklet collection ? > and > the Pharo technology booklet collection ? > > > Pharology / Pharocraft > > > cheers -ben > > > > > > > >

March 4, 2018

Re: [Pharo-users] Ever growing image

by Sean P. DeNigris

Pharo Smalltalk Users mailing list wrote > Estaban, > I guess there are some advantages to shrink the image (as compared to > bootstrapping from a minimal image) Also, they are not mutually exclusive. While bootstrapping seems a clear choice for building images. A tool could then scan an image (e.g. for deployment) and pare it down to just what's needed. IIRC Self might have done some work in this directionâ¦ ----- Cheers, Sean -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

March 4, 2018

Re: [Pharo-dev] Looking for names for the booklet collection

by Benoit St-Jean

Why not simply: Pharo Tools & TechnologiesPharo Language & Environment ----------------- BenoÃ®t St-Jean Yahoo! Messenger: bstjean Twitter: @BenLeChialeux Pinterest: benoitstjean Instagram: Chef_Benito IRC: lamneth Blogue: endormitoire.wordpress.com "A standpoint is an intellectual horizon of radius zero".Â (A. Einstein) On Sunday, March 4, 2018, 10:30:46 AM EST, Ben Coman <btc(a)openinworld.com> wrote: On 4 March 2018 at 20:21, Stephane Ducasse <stepharo.self(a)gmail.com> wrote: Hi I would like to make a distinction between booklet on Pharo technologies (Smacc, Voyage, Scraping ...) and the booklets more oriented towards teaching something with pharo (building an interpreter, a reflective language...) Pharo Applications / Inside PharoÂ Over Pharo / Under PharoÂ Right now we have The Pharo Booklet Collection. And I'm looking for two names the Pharo academic booklet collection ? and the Pharo technology booklet collection ? Pharology /Â PharocraftÂ cheers -benÂ Â Â

March 4, 2018

Re: [Pharo-users] [Pharo-dev] Looking for names for the booklet collection

by Ben Coman

On 4 March 2018 at 20:21, Stephane Ducasse <stepharo.self(a)gmail.com> wrote: > Hi > > I would like to make a distinction between booklet on Pharo > technologies (Smacc, Voyage, Scraping ...) and the booklets more > oriented towards teaching something with pharo (building an > interpreter, a reflective language...) > Pharo Applications / Inside Pharo Over Pharo / Under Pharo > Right now we have The Pharo Booklet Collection. > And I'm looking for two names > > the Pharo academic booklet collection ? > and > the Pharo technology booklet collection ? Pharology / Pharocraft cheers -ben > >

March 4, 2018

Re: [Pharo-users] Ever growing image

by Ben Coman

On 4 March 2018 at 20:08, Hilaire <hilaire(a)drgeo.eu> wrote: > Le 04/03/2018 Ã 11:13, Esteban Lorenzano a Ã©crit : > >> In our community, Pavel is the person that has the bigger experience on >> shrinking process images. I followed his work for years and I know the >> fragility of the process. Basically each new addition/removal was breaking >> it and needing dependency tracking, etc. Now is the opposite: you just add >> what you want, and you are sure the resulting image is a) healthy and b) >> identical when running. >> >> > Indeed it is fragile. And given the latest image size, not sure it could > lead to satisfactory results. > I understood that to mean that getting a minimal image via automated stripping was more fragile than bootstrapping, and with bootstrapping we are now on a better path. And Pharo is transitioning a few tools. Nautilus-->Calypso and Morphic-->Bloc. Obviously old and new overlap for a time. So it should get better. cheers -ben

March 4, 2018