perl.fwp

perl.fwp http://www.nntp.perl.org/group/perl.fwp/ ... Copyright 1998-2013 perl.org Thu, 23 May 2013 22:14:47 +0000 ask@perl.org FW: 3/15/2013 10:26:49 AM by Andrew Savige http://www.occamobile.com/zhvrm/htdza/hsp/gr/vo 3/15/2013 10:26:49 AM . Andrew Savige http://www.nntp.perl.org/group/perl.fwp/2013/03/msg4214.html Fri, 15 Mar 2013 09:27:01 +0000 Re: seeking golfing advice by Smylers Aristotle Pagaltzis writes: > And if you have an array to work with in the first place, you can also > > @array[map 1+$_*2, 0..$#array/2] > > which is 3 characters longer than the grep version I think that actually gives you the even elements. For the odd elements (which are even array indices, in Perl's terms) you don't need the C< 1+> in there, saving 3 characters. @array[map$_*2,0..$#array/2] The shortest variant like that I've found for even characters is: @array[map$_*2-1,1..@array/2] @array is one character shorter than $#array, but to avoid getting an unwanted undef element when @array has an even number of elements in it you need to start at 1 rather than 0, which makes the subtraction necessary. Smylers -- http://twitter.com/Smylers2 http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4213.html Sat, 19 May 2012 03:19:25 +0000 Re: seeking golfing advice by John Douglas Porter > From: Aristotle Pagaltzis <pagaltzis@gmx.de> > Subject: Re: seeking golfing advice > To: fwp@perl.org > Date: Friday, May 18, 2012, 5:29 AM > * Steve Fink <sphink@gmail.com> > [2012-05-18 10:25]: > > On Thu, May 17, 2012 at 3:14 AM, Aristotle Pagaltzis > <pagaltzis@gmx.de> > wrote: > > > * Mike Erickson <mee@quidquam.com> > [2012-05-16 15:45]: > > > > If you don't care about order, but just want > those elements, you > > > > can also do: > > > > > > > > keys%{{@a}} > > > > > > There is more than order that gets lost. If you > use `keys` you also > > > get everything back stringified – undefs are > lost and references > > > break. If you use `values` these problems go > away… except that to > > > get the odd-index elements from it you have to > `reverse` the array, > > > at which point a not-especially-golfed grep is > shorter. > > > > So you'd want > > > >  values%{{1,@a}} > > > > then > > D’oh! D::oh is right. You get an unwanted extra undef at the end of such list. http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4212.html Fri, 18 May 2012 06:17:56 +0000 Re: seeking golfing advice by Aristotle Pagaltzis * Steve Fink <sphink@gmail.com> [2012-05-18 10:25]: > On Thu, May 17, 2012 at 3:14 AM, Aristotle Pagaltzis <pagaltzis@gmx.de> wrote: > > * Mike Erickson <mee@quidquam.com> [2012-05-16 15:45]: > > > If you don't care about order, but just want those elements, you > > > can also do: > > > > > > keys%{{@a}} > > > > There is more than order that gets lost. If you use `keys` you also > > get everything back stringified – undefs are lost and references > > break. If you use `values` these problems go away… except that to > > get the odd-index elements from it you have to `reverse` the array, > > at which point a not-especially-golfed grep is shorter. > > So you'd want > > values%{{1,@a}} > > then D’oh! http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4211.html Fri, 18 May 2012 02:29:29 +0000 Re: seeking golfing advice by Steve Fink On Thu, May 17, 2012 at 3:14 AM, Aristotle Pagaltzis <pagaltzis@gmx.de> wrote: > * Mike Erickson <mee@quidquam.com> [2012-05-16 15:45]: >> If you don't care about order, but just want those elements, you can >> also do: >> >> keys%{{@a}} > > There is more than order that gets lost. If you use `keys` you also get > everything back stringified – undefs are lost and references break. If > you use `values` these problems go away… except that to get the odd- > index elements from it you have to `reverse` the array, at which point > a not-especially-golfed grep is shorter. So you'd want values%{{1,@a}} then http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4210.html Fri, 18 May 2012 01:24:18 +0000 Re: seeking golfing advice by Aristotle Pagaltzis * Pau Amma <pauamma@gundo.com> [2012-05-16 14:55]: > If, as it sounds, you want to balance golfiness and strictness, you > could also say: > > @array[grep $_%2, keys @array] > > (or @array[grep $_%2^1, keys @array] if you set $[ to 1 - but you > didn't do that, right? :-) ) Btw, `keys@foo` and `0..$#foo` are equally long… but the latter works with old perls (advantage production) *and* looks more line-noisy (advantage golf). And if you have an array to work with in the first place, you can also @array[map 1+$_*2, 0..$#array/2] which is 3 characters longer than the grep version in exchange for doing half as much work. (For even elements, the map and grep solutions would yield exactly equally long code, with half-as-much-work still applying.) -- *AUTOLOAD=*_;sub _{s/$/$"/;s/(.*):://;wantarray//substr$_,-1,1,",$/";print;$1} &Just->another->Perl->hack; #Aristotle Pagaltzis // <http://plasmasturm.org/> http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4209.html Thu, 17 May 2012 03:28:29 +0000 Re: seeking golfing advice by Aristotle Pagaltzis * Mike Erickson <mee@quidquam.com> [2012-05-16 15:45]: > If you don't care about order, but just want those elements, you can > also do: > > keys%{{@a}} There is more than order that gets lost. If you use `keys` you also get everything back stringified – undefs are lost and references break. If you use `values` these problems go away… except that to get the odd- index elements from it you have to `reverse` the array, at which point a not-especially-golfed grep is shorter. -- *AUTOLOAD=*_;sub _{s/$/$"/;s/(.*):://;wantarray//substr$_,-1,1,",$/";print;$1} &Just->another->Perl->hack; #Aristotle Pagaltzis // <http://plasmasturm.org/> http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4208.html Thu, 17 May 2012 03:15:10 +0000 Re: seeking golfing advice by Ronald J Kimball On Wed, May 16, 2012 at 04:40:40AM -0700, John Douglas Porter wrote: > And of course, use grep, as others have said. > > @list[ grep !$_%2, 0..$#list ]; > > that gets you every other element, beginning with the first. ! has higher precedence than %, so this actually gets you just the first element. You need to add parentheses to get the correct result: @list[grep!($_%2),0..$#list]; There are a couple ways to shave a character from that: @list[grep$_%2-1,0..$#list]; @list[grep$_+1&1,0..$#list]; Ronald http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4207.html Wed, 16 May 2012 08:22:42 +0000 AW: seeking golfing advice by Moritz, Georg > btw here is an example : > > the code, applied on (1, 2, 3, 4) would return (1, 3). Thanks so you want to check every element for oddity of its value, not its index, right? @list = grep{$_%2}@array; cheers, 0--gg- > On 16 May 2012 13:15, damien krotkine <dkrotkine@gmail.com> wrote: > > Hi, > > > > I'm using this code to get a list of only the odd elements of an > > array. The resulting list must have the same order as the array. > > > > map { state $f; ($_) x (++$f%2) }  @array; > > > > I'm looking for advice to make it shorter or nicer. Everything in perl > > 5.12 is allowed, but must pass use strict. I've failed at using the > > '..' operator to act as a flip/flop operator... > > > > thanks, > > dams > http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4206.html Wed, 16 May 2012 07:48:22 +0000 Re: seeking golfing advice by Mike Erickson On 05/16/2012 07:46 AM, damien krotkine wrote: > Hi all, > > thanks for the quick answers :) > > first of all, despite my attempt to clear things up with an example, I > failed :) What I wante is "every other element, beginning with the > first", so : > > ( 'foo', 3, 42, 'bar) should become ( 'foo', 42). If you don't care about order, but just want those elements, you can also do: keys%{{@a}} {@a} being a hash ref constructed from @a %{ } dereferencing that hash ref keys pulling out the keys, ie. the odd elements of the orig. list hth, Mike http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4205.html Wed, 16 May 2012 06:41:42 +0000 Re: seeking golfing advice by Pau Amma On Wed, May 16, 2012 12:25 pm, damien krotkine wrote: > On 16 May 2012 14:02, Peter Makholm <peter@makholm.net> wrote: > [ ... ] > >> So basically you are trading 8 characters for readability and probably >> speed. Why do you want that? > > For fun, purely. I'll stick with $f % 2 for now, it seems a right > balance compared to the code lying around. If, as it sounds, you want to balance golfiness and strictness, you could also say: @array[grep $_%2, keys @array] (or @array[grep $_%2^1, keys @array] if you set $[ to 1 - but you didn't do that, right? :-) ) http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4204.html Wed, 16 May 2012 05:52:17 +0000 Re: seeking golfing advice by damien krotkine On 16 May 2012 14:02, Peter Makholm <peter@makholm.net> wrote: > damien krotkine <dkrotkine@gmail.com> writes: > >> Indeed grep is much better. As the code is used in a more complex >> structured I got lost and confused and ended up using map, blah. >> >> $|-- was what I was looking for :) > > No, reading my posts again it I see that it clearly doesn't do what you > ask for. You are actually looking for --$|. Oops yes, --$| indeed, sorry. [ ... ] > So basically you are trading 8 characters for readability and probably > speed. Why do you want that? For fun, purely. I'll stick with $f % 2 for now, it seems a right balance compared to the code lying around. dams http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4203.html Wed, 16 May 2012 05:25:36 +0000 Re: seeking golfing advice by Peter Makholm damien krotkine <dkrotkine@gmail.com> writes: > Indeed grep is much better. As the code is used in a more complex > structured I got lost and confused and ended up using map, blah. > > $|-- was what I was looking for :) No, reading my posts again it I see that it clearly doesn't do what you ask for. You are actually looking for --$|. > Finally, one question : why is $|-- not recommended in production, if > the following conditions are met : I'm not running in threads, not in > an event-loop that might be affected by $| being set, and I'll take > care of resetting $| appropriately at the end. It depends on an obscure, undocumented feature of a magic variable, which unless used correct may have an unintended action at a distance. This makes the code hard to maintain for the next developer (which might be youself 14 days down the road). What do you think you are optimizing for? I would guess that the $| is also a bit slower, as it needs to at least test if the filehandle needs to be flushed even though you know that no one had the chance to write to it. So basically you are trading 8 characters for readability and probably speed. Why do you want that? //Makholm http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4202.html Wed, 16 May 2012 05:03:14 +0000 Re: seeking golfing advice by damien krotkine Hi all, thanks for the quick answers :) first of all, despite my attempt to clear things up with an example, I failed :) What I wante is "every other element, beginning with the first", so : ( 'foo', 3, 42, 'bar) should become ( 'foo', 42). Indeed grep is much better. As the code is used in a more complex structured I got lost and confused and ended up using map, blah. $|-- was what I was looking for :) About golfing and strictness I am well aware that the two are incompatible. What I originally meant is to get something with a sane balance between the two. Finally, one question : why is $|-- not recommended in production, if the following conditions are met : I'm not running in threads, not in an event-loop that might be affected by $| being set, and I'll take care of resetting $| appropriately at the end. Even in this case, wouldn't you recommend using $| ? Thanks again On 16 May 2012 13:36, Peter Makholm <peter@makholm.net> wrote: > Peter Makholm <peter@makholm.net> writes: > >> damien krotkine <dkrotkine@gmail.com> writes: >> >>> I'm using this code to get a list of only the odd elements of an >>> array. The resulting list must have the same order as the array. >>> >>> map { state $f; ($_) x (++$f%2) }  @array; > > Wow, you asked for golfing advice in the subject and a nice solution in > the actual text. Those requirements are quite often very incompatible. > >> If you want only to get some elements of a list is is much more obvious >> to use grep instead of map: >> >>   grep { ++$f%2 } @array > > This is probably as nice as it gets. For strictness I would just declare > $f as a lexical variable just outside the grep. But asking for golfing > advice is not compliant with strictness or niceness. > >> And remove unneeded syntax >> >>   grep$|--,@array > > I think this would be the golfing solution, but as with everything alse > related to perl golfing don't use it in production code. > > //Makholm > http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4201.html Wed, 16 May 2012 04:46:43 +0000 Re: seeking golfing advice by John Douglas Porter And of course, use grep, as others have said. @list[ grep !$_%2, 0..$#list ]; that gets you every other element, beginning with the first. --- On Wed, 5/16/12, John Douglas Porter <johndporter@yahoo.com> wrote: > From: John Douglas Porter <johndporter@yahoo.com> > Subject: Re: seeking golfing advice > To: fwp@perl.org > Date: Wednesday, May 16, 2012, 7:35 AM > It's not clear whether you want > "every other element, beginning with the first" or "every > numeric element with the property 'odd'".  Your example > doesn't clear that up at all. :-) > > If it's the latter you want: > > map { $_ & 1 ? $_ : () } @l; > > > --- On Wed, 5/16/12, damien krotkine <dkrotkine@gmail.com> > wrote: > > > From: damien krotkine <dkrotkine@gmail.com> > > Subject: Re: seeking golfing advice > > To: fwp@perl.org > > Date: Wednesday, May 16, 2012, 7:19 AM > > btw here is an example : > > > > the code, applied on (1, 2, 3, 4) would return (1, 3). > > Thanks > > > > On 16 May 2012 13:15, damien krotkine <dkrotkine@gmail.com> > > wrote: > > > Hi, > > > > > > I'm using this code to get a list of only the odd > > elements of an > > > array. The resulting list must have the same order > as > > the array. > > > > > > map { state $f; ($_) x (++$f%2) }  @array; > > > > > > I'm looking for advice to make it shorter or > nicer. > > Everything in perl > > > 5.12 is allowed, but must pass use strict. I've > failed > > at using the > > > '..' operator to act as a flip/flop operator... > > > > > > thanks, > > > dams > > > http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4200.html Wed, 16 May 2012 04:40:51 +0000 Re: seeking golfing advice by Peter Makholm Peter Makholm <peter@makholm.net> writes: > damien krotkine <dkrotkine@gmail.com> writes: > >> I'm using this code to get a list of only the odd elements of an >> array. The resulting list must have the same order as the array. >> >> map { state $f; ($_) x (++$f%2) } @array; Wow, you asked for golfing advice in the subject and a nice solution in the actual text. Those requirements are quite often very incompatible. > If you want only to get some elements of a list is is much more obvious > to use grep instead of map: > > grep { ++$f%2 } @array This is probably as nice as it gets. For strictness I would just declare $f as a lexical variable just outside the grep. But asking for golfing advice is not compliant with strictness or niceness. > And remove unneeded syntax > > grep$|--,@array I think this would be the golfing solution, but as with everything alse related to perl golfing don't use it in production code. //Makholm http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4199.html Wed, 16 May 2012 04:36:52 +0000 Re: seeking golfing advice by John Douglas Porter It's not clear whether you want "every other element, beginning with the first" or "every numeric element with the property 'odd'". Your example doesn't clear that up at all. :-) If it's the latter you want: map { $_ & 1 ? $_ : () } @l; --- On Wed, 5/16/12, damien krotkine <dkrotkine@gmail.com> wrote: > From: damien krotkine <dkrotkine@gmail.com> > Subject: Re: seeking golfing advice > To: fwp@perl.org > Date: Wednesday, May 16, 2012, 7:19 AM > btw here is an example : > > the code, applied on (1, 2, 3, 4) would return (1, 3). > Thanks > > On 16 May 2012 13:15, damien krotkine <dkrotkine@gmail.com> > wrote: > > Hi, > > > > I'm using this code to get a list of only the odd > elements of an > > array. The resulting list must have the same order as > the array. > > > > map { state $f; ($_) x (++$f%2) }  @array; > > > > I'm looking for advice to make it shorter or nicer. > Everything in perl > > 5.12 is allowed, but must pass use strict. I've failed > at using the > > '..' operator to act as a flip/flop operator... > > > > thanks, > > dams > http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4198.html Wed, 16 May 2012 04:35:48 +0000 Re: seeking golfing advice by Peter Makholm damien krotkine <dkrotkine@gmail.com> writes: > I'm using this code to get a list of only the odd elements of an > array. The resulting list must have the same order as the array. > > map { state $f; ($_) x (++$f%2) } @array; If you want only to get some elements of a list is is much more obvious to use grep instead of map: grep { ++$f%2 } @array Then use the magical flip-flop variable: grep { $|-- } @array And remove unneeded syntax grep$|--,@array //Makholm http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4197.html Wed, 16 May 2012 04:31:26 +0000 Re: seeking golfing advice by Daniel Cutter On 16.05.2012 13:19, damien krotkine wrote: > btw here is an example : > > the code, applied on (1, 2, 3, 4) would return (1, 3). Thanks > > On 16 May 2012 13:15, damien krotkine<dkrotkine@gmail.com> wrote: >> Hi, >> >> I'm using this code to get a list of only the odd elements of an >> array. The resulting list must have the same order as the array. >> >> map { state $f; ($_) x (++$f%2) } @array; >> >> I'm looking for advice to make it shorter or nicer. Everything in perl >> 5.12 is allowed, but must pass use strict. I've failed at using the >> '..' operator to act as a flip/flop operator... >> >> thanks, >> dams Isn't this what grep is for? 1 #!perl 2 use strict; 3 my @array=(1,2,3,4); 4 my $f; 5 my @result = grep {++$f%2} @array; 6 print "@result\n"; -- *Daniel Cutter* s/\b[^a]/\u$&/g,s;$;,;,print for join$,,map{('acehjklnoprstu' =~m(.)g,$")[/\d/?$_:hex]}q(4dbce078c32ae92a6e30152aff)=~m(.)g http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4196.html Wed, 16 May 2012 04:29:36 +0000 Re: seeking golfing advice by damien krotkine btw here is an example : the code, applied on (1, 2, 3, 4) would return (1, 3). Thanks On 16 May 2012 13:15, damien krotkine <dkrotkine@gmail.com> wrote: > Hi, > > I'm using this code to get a list of only the odd elements of an > array. The resulting list must have the same order as the array. > > map { state $f; ($_) x (++$f%2) }  @array; > > I'm looking for advice to make it shorter or nicer. Everything in perl > 5.12 is allowed, but must pass use strict. I've failed at using the > '..' operator to act as a flip/flop operator... > > thanks, > dams http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4195.html Wed, 16 May 2012 04:19:09 +0000 seeking golfing advice by damien krotkine Hi, I'm using this code to get a list of only the odd elements of an array. The resulting list must have the same order as the array. map { state $f; ($_) x (++$f%2) } @array; I'm looking for advice to make it shorter or nicer. Everything in perl 5.12 is allowed, but must pass use strict. I've failed at using the '..' operator to act as a flip/flop operator... thanks, dams http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4194.html Wed, 16 May 2012 04:16:01 +0000 The History of Acme::Bleach and Acme::EyeDrops by Andrew Savige The story behind Acme::Bleach and its many cousins:  http://www.perlmonks.org/?node_id=967004 Feedback and anecdotes welcome. Thanks, /-\ http://www.nntp.perl.org/group/perl.fwp/2012/05/msg4193.html Wed, 02 May 2012 05:56:32 +0000 Re: Secret operators: the documentation by Michael R . Wolf On Mar 16, 2012, at 4:44 AM, Philippe Bruhat (BooK) wrote: > A few years back, I started to write a manual page about Perl secret operators, > with the goal of getting it into the official Perl documentation at some point. A few comments… 1. It would be nice to do a bit of documentation on *why* or *how* some of these work. Perhaps a Deparse would be sufficient (as in Eskimo greeting), but English is also a good tool. For starters, I didn't figure out how "Ornate double-bladed sword worked". I'm sure I could have created the trail alone, but it would be nice to follow someone else's blaze. 2. Given how dangerous this one could be (to a psyche) if researched deeply (years of therapy…) =( )= Goatse scalar / list context I'd suggest another name -- Saturn. Yes, snicker if you will. Saturn *is* the son of the Greek deity Uranus, but that's only a 2nd order, inside joke. The operator looks like Saturn, even when spaces are inserted (as will be likely with syntax formatting editors or perltidy(1))! =( )= Saturn scalar / list context = ( ) = Saturn scalar / list context Keep the old name if you wish, but add one that's more psychologically healthy, too!!! (P.S. Thanks for the warning. That's just plain *responsible* behavior to the community!!! One image could ruin someone's whole view of Perl.) Michael -- Michael R. Wolf All mammals learn by playing! MichaelRWolf@att.net http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4192.html Fri, 06 Apr 2012 18:26:31 +0000 Re: Secret operators: the documentation by John Douglas Porter Philippe Bruhat (BooK) <philippe.bruhat@free.fr> wrote: > Andrew Savige wrote: > > > > I wonder if --$| and $|--, ... described > > by japhy as "the magical flip flop variable" > > qualifies as a secret operator? > > My rule has been to keep > only the well-known operators, or the ones that had a > nickname that > corresponded to their looks, not their function. > > Under that rulle, the magical flip-flop wouldn't have fit. Not to mention the fact that it's not an operator. :-) -- john "many jars" porter http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4191.html Tue, 03 Apr 2012 04:55:20 +0000 Re: Secret operators: the documentation by Philippe Bruhat On Tue, Apr 03, 2012 at 03:43:54AM -0700, Andrew Savige wrote: > > > I wonder if --$| and $|--, very popular in golf, and described > by japhy as "the magical flip flop variable" at: > >  http://www.nntp.perl.org/group/perl.fwp/2002/01/msg1367.html > > qualifies as a secret operator? > I have had several requests for adding more obscure constructs (see https://github.com/book/perlsecret/issues). My rule has been to keep only the well-known operators, or the ones that had a nickname that corresponded to their looks, not their function. Under that rulle, the magical flip-flop wouldn't have fit. Anyway, I guess others can decide what gets in when the branch merged into blead. -- Philippe Bruhat (BooK) Out of the worst can often come the best. (Moral from Groo The Wanderer #57 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4190.html Tue, 03 Apr 2012 04:35:05 +0000 Re: Secret operators: the documentation by Philippe Bruhat On Mon, Apr 02, 2012 at 06:28:56PM +0200, Alexis Sukrieh wrote: > Le 16 mars 2012 12:44, Philippe Bruhat (BooK) > <philippe.bruhat@free.fr> a écrit : > > So, > > > > A few years back, I started to write a manual page about Perl secret operators, > > with the goal of getting it into the official Perl documentation at some point. > [...] > > Patches welcome. > > > > When it's stabilized enough, I'll send a patch to p5p. > > Nice work :) > > I have a question though; > > Did you change your mind about the "A word of warning" section? It > sounds that it won't fit well in the official Perl documentation ;) > I've pushed a branch on the Perl source tree, and Abigail already patched the module a bit. http://perl5.git.perl.org/perl.git/shortlog/refs/heads/book/perlsecret The "word of warning" still holds. The page is specifically not listed in the main perl.pod manual page. The idea is to hide it a little, so that people who know about it can easily point inquiring minds to it, while not making these "official". I also wrote a test script (t/japh/secret.t) and it helped a lot in refining exactly how and when each of those worked. -- Philippe Bruhat (BooK) "Did I err?" (Groo, in too many issues to count - ...and *YES* he did!) http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4189.html Tue, 03 Apr 2012 04:31:41 +0000 Re: Secret operators: the documentation by Andrew Savige I wonder if --$| and $|--, very popular in golf, and described by japhy as "the magical flip flop variable" at:  http://www.nntp.perl.org/group/perl.fwp/2002/01/msg1367.html qualifies as a secret operator? /-\ http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4188.html Tue, 03 Apr 2012 03:44:03 +0000 Re: Secret operators: the documentation by Pau Amma On Mon, April 2, 2012 4:28 pm, Alexis Sukrieh wrote: > Le 16 mars 2012 12:44, Philippe Bruhat (BooK) > <philippe.bruhat@free.fr> a écrit : >> So, >> >> A few years back, I started to write a manual page about Perl secret >> operators, > [...] > I have a question though; > > Did you change your mind about the "A word of warning" section? It > sounds that it won't fit well in the official Perl documentation ;) Version I saw last week-end includes: === You're welcome to try these at home, but they might not be safe for work! === Is that what you were thinking of? http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4187.html Mon, 02 Apr 2012 11:14:55 +0000 Re: Secret operators: the documentation by Alexis Sukrieh Le 16 mars 2012 12:44, Philippe Bruhat (BooK) <philippe.bruhat@free.fr> a écrit : > So, > > A few years back, I started to write a manual page about Perl secret operators, > with the goal of getting it into the official Perl documentation at some point. [...] > Patches welcome. > > When it's stabilized enough, I'll send a patch to p5p. Nice work :) I have a question though; Did you change your mind about the "A word of warning" section? It sounds that it won't fit well in the official Perl documentation ;) My two cents! http://www.nntp.perl.org/group/perl.fwp/2012/04/msg4186.html Mon, 02 Apr 2012 09:29:08 +0000 Re: Secret operators: the documentation by Daniel Bruder Also don't forget it is expandable, and as it is, still (erotic?) perl :-) perl -e 'print ~~<> => ~~~~<> => ~~~~~~<> => ~~<>+0' On 16 March 2012 12:44, Philippe Bruhat (BooK) <philippe.bruhat@free.fr>wrote: > So, > > A few years back, I started to write a manual page about Perl secret > operators, > with the goal of getting it into the official Perl documentation at some > point. > > Somehow I got interested in that again, and started to really work on it. > The current work in progress is availabled at: > https://github.com/book/perlsecret > > I've already included most of the feedback from the discussions on ~~<>. > > Patches welcome. > > When it's stabilized enough, I'll send a patch to p5p. > > -- > Philippe Bruhat (BooK) > > Too many believe only in the belief. > (Moral from Groo The Wanderer #58 > (Epic)) > http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4185.html Fri, 16 Mar 2012 05:05:37 +0000 Secret operators: the documentation by Philippe Bruhat So, A few years back, I started to write a manual page about Perl secret operators, with the goal of getting it into the official Perl documentation at some point. Somehow I got interested in that again, and started to really work on it. The current work in progress is availabled at: https://github.com/book/perlsecret I've already included most of the feedback from the discussions on ~~<>. Patches welcome. When it's stabilized enough, I'll send a patch to p5p. -- Philippe Bruhat (BooK) Too many believe only in the belief. (Moral from Groo The Wanderer #58 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4184.html Fri, 16 Mar 2012 04:44:46 +0000 Re: The sperm secret operator: is it new? by Philippe Bruhat On Thu, Mar 15, 2012 at 10:40:17AM +0100, Dmitry Karasik wrote: > > > Does that mean I have a dirty mind? > > At least not dirtier than the inventor of the =()= (unless that was you ;) I think the first person using =()= (Randal?) is not the same as the first person naming it in a Perl context. Both probably have been invented independently, as goatse was a popular meme at some point, and people collected references to it. It's not suprising that a minimalist ascii-art version appeared. And that it looked like Perl code. -- Philippe Bruhat (BooK) The man who most obeys the king is the man who gets crowned. (Moral from Groo The Wanderer #13 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4183.html Fri, 16 Mar 2012 04:43:52 +0000 Re: The sperm secret operator: is it new? by Philippe Bruhat On Thu, Mar 15, 2012 at 03:45:47PM +0100, Dmitry Karasik wrote: > >>> ~~<> > >> Looks more like a "kite" operator to me. > > Does that mean I have a dirty mind? > > That means that there's no such thing as a four-squared sperm! > Not that =()= resembles much to a... Hrmpf. See also http://en.wikipedia.org/wiki/Sperm. The side view is four-squared enough for me. The limitations of ASCII shouldn't limit our imaginations! -- Philippe Bruhat (BooK) Too many believe only in the belief. (Moral from Groo The Wanderer #58 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4182.html Thu, 15 Mar 2012 08:35:35 +0000 Re: The sperm secret operator: is it new? by Dmitry Karasik >>> ~~<> >> Looks more like a "kite" operator to me. > Does that mean I have a dirty mind? That means that there's no such thing as a four-squared sperm! (ps my previous answer apparently didn't pass to the list, this is a shorter version of it anyway :) -- Sincerely, Dmitry Karasik http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4181.html Thu, 15 Mar 2012 07:45:56 +0000 Re: The sperm secret operator: is it new? by Dmitry Karasik > >> While doing some tests/research on secret operators, I stumbled upon >> this >> one in my one-liners: >> >> ~~<> >> >> Obviously, this should be named "the sperm operator". >> Looks more like a "kite" operator to me. > Does that mean I have a dirty mind? At least not dirtier than the inventor of the =()= (unless that was you ;) ... anyway I think it'll be adopted better as "kite", and well also, where did you see a four-squared sperm? :) -- Sincerely, Dmitry Karasik http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4180.html Thu, 15 Mar 2012 07:41:14 +0000 Re: The sperm secret operator: is it new? by Daniel Cutter I would think it means you live in an area where it's not very windy. *Daniel Cutter* s/\b[^a]/\u$&/g,s;$;,;,print for join$,,map{('acehjklnoprstu' =~m(.)g,$")[/\d/?$_:hex]}q(4dbce078c32ae92a6e30152aff)=~m(.)g Am 15.03.2012 09:22, schrieb Philippe Bruhat (BooK): > On Thu, Mar 15, 2012 at 06:25:49AM +0100, Dmitry Karasik wrote: >>>> While doing some tests/research on secret operators, I stumbled upon this >>>> one in my one-liners: >>>> >>>> ~~<> >>>> >>>> Obviously, this should be named "the sperm operator". >> >> Looks more like a "kite" operator to me. >> > Does that mean I have a dirty mind? > http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4179.html Thu, 15 Mar 2012 02:53:30 +0000 Re: The sperm secret operator: is it new? by Philippe Bruhat On Thu, Mar 15, 2012 at 06:25:49AM +0100, Dmitry Karasik wrote: > >> > >> While doing some tests/research on secret operators, I stumbled upon this > >> one in my one-liners: > >> > >> ~~<> > >> > >> Obviously, this should be named "the sperm operator". > > > Looks more like a "kite" operator to me. > Does that mean I have a dirty mind? -- Philippe Bruhat (BooK) Law is the best deterrent to Justice. (Moral from Groo The Wanderer #90 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4178.html Thu, 15 Mar 2012 01:23:08 +0000 Re: The sperm secret operator: is it new? by Dmitry Karasik >> Hi, >> >> While doing some tests/research on secret operators, I stumbled upon this >> one in my one-liners: >> >> ~~<> >> >> Obviously, this should be named "the sperm operator". Looks more like a "kite" operator to me. -- Sincerely, Dmitry Karasik http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4177.html Wed, 14 Mar 2012 22:25:59 +0000 Re: The sperm secret operator: is it new? by Yitzchak Scott-Thoennes On Wed, Mar 14, 2012 at 3:50 PM, Philippe Bruhat (BooK) <philippe.bruhat@free.fr> wrote: > Frankly, I think this could be considered a bug. Both the left-facing > and right-facing versions of the inchworm on a stick should work on > all integers in Perl. Complement two arithmetics demand it! Now, the > question is, how long has this been broken in Perl? Forever? I don't consider it a bug. ~ has to either assume signed or unsigned. You get a choice by whether you do it under the scope of use integer (implicit: comma signed) or not. http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4176.html Wed, 14 Mar 2012 16:02:49 +0000 Re: The sperm secret operator: is it new? by Philippe Bruhat On Wed, Mar 14, 2012 at 01:46:34PM -0700, Andrew Savige wrote: > > [ ~~ vs. scalar ] > > The ~~ secret operator is old hat, good ol' inchworm: > >  http://www.catonmat.net/blog/secret-perl-operators/#inchworm > > BooK's innovation is to add <> and <>+0 to the end of it. > > BTW, in addition to inchworm-on-a-stick ~- to subtract one, > I often use the converse -~ to add one (though only in Ruby > and Python, not usually Perl). For example, -~1 produces 2 > in Ruby and Python, but -4,294,967,294 in Perl. > It works in C too. I was doing some research on secret operators today, and I discovered the effects of the other inchworm-on-a-stick, and the fact that both operators are broken for half the integers in Perl. ~- only decrements integers greater than 0 in Perl. -~ only increments integers lesser than 0 in Perl. According to Abigail and rgs, it's probably because ~ must also handle strings. Abigail and I looked at the source of pp_negate, and it seems like it does the right thing, so ~ seems to be the culprit. (I see that tzchak Scott-Thoennes has provided a thorough answer in another mail.) Frankly, I think this could be considered a bug. Both the left-facing and right-facing versions of the inchworm on a stick should work on all integers in Perl. Complement two arithmetics demand it! Now, the question is, how long has this been broken in Perl? Forever? -- Philippe Bruhat (BooK) The learned man makes a mistake but once... but the truly stupid keep practicing until they get it right. (Moral from Groo The Wanderer #75 (Epic)) http://www.nntp.perl.org/group/perl.fwp/2012/03/msg4175.html Wed, 14 Mar 2012 15:50:55 +0000