Re: steps of a path
Apologies: the first code example in my previous email won't check for a
given directory, and will print out bogus paths:
~$ echo "/Users/none/bogus_dir/" | raku -e 'for lines.IO -> $a is copy
{$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
$*SPEC.rootdir};'
/Users/none/bogus_dir/
/Users/none
/Users
/
The second code example will first check for a given directory:
~$ echo "/Users/admin/Documents/" | raku -e 'for lines.IO -> $a is copy {if
$a.d {$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
$*SPEC.rootdir}};'
/Users/admin/Documents/
/Users/admin
/Users
/
~$ echo "/Users/none/bogus_dir/" | raku -e 'for lines.IO -> $a is copy {if
$a.d {$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
$*SPEC.rootdir}};'
~$
https://docs.raku.org/type/IO::Path#File_test_operators
HTH, Bill.
On Wed, Sep 7, 2022 at 7:39 AM William Michels
wrote:
> Hi Marc,
>
> Does this do what you want? I've omitted the call to `run` and used mostly
> IO::Path calls instead:
>
> ~$ echo "/Users/admin/logs" | raku -e 'for lines.IO -> $a is copy
> {$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
> $*SPEC.rootdir;};'
>
> #returns:
>
> /Users/admin/logs
> /Users/admin
> /Users
> /
>
> Note, above won't actually check if the given directory is valid--it only
> checks the parents. To check a given directory first, try the following:
>
> ~$ echo "/Users/admin/bogus_dir/" | raku -e 'for lines.IO -> $a is copy
> {if $a.d {$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
> $*SPEC.rootdir}};'
>
> #returns nothing for `bogus_dir`
>
> HTH, Bill.
>
>
> On Mon, Sep 5, 2022 at 1:56 PM Marc Chantreux wrote:
>
>> I love this one. I used uniq and run so the whole script can be run from
>> raku (except the xargs ls avoid the ARG_MAX error)
>>
>> <<. raku -e 'run < ls -lUd >, unique map {(.IO, *.parent …^
>> "/")>>.Str.Slip}, lines'
>> /var/log/messages
>> /var/log/auth.log
>>
>> regards
>>
>> --
>> Marc Chantreux
>> Pôle de Calcul et Services Avancés à la Recherche (CESAR)
>> http://annuaire.unistra.fr/p/20200
>>
>
Re: steps of a path
On Wed, Sep 7, 2022 at 6:27 PM Parrot Raiser <1parr...@gmail.com> wrote: > > > > That said, right now gmail is claiming whipupitude is misspelled... > > > An alternative is "whipitupitude" (the difference being the first "it". > > Given the examples I've seen over the years, there's a need for an > opposite to "idiomatic", for programming that arrives at a solution by > a Rube Goldberg/Heath Robinson sort of convoluted and unnecessary > path, or utterly abuses the language in a fashion that contradicts its > underlying purpose or philosophy (writing video games in sed or > invoicing programs in Lisp). "Idiotmatic" suggests itself. :-)* > Sure you don't want "idiosyncratic"? Eirik
Re: steps of a path
> > That said, right now gmail is claiming whipupitude is misspelled... > An alternative is "whipitupitude" (the difference being the first "it". Given the examples I've seen over the years, there's a need for an opposite to "idiomatic", for programming that arrives at a solution by a Rube Goldberg/Heath Robinson sort of convoluted and unnecessary path, or utterly abuses the language in a fashion that contradicts its underlying purpose or philosophy (writing video games in sed or invoicing programs in Lisp). "Idiotmatic" suggests itself. :-)*
Re: steps of a path
Hi Marc,
Does this do what you want? I've omitted the call to `run` and used mostly
IO::Path calls instead:
~$ echo "/Users/admin/logs" | raku -e 'for lines.IO -> $a is copy
{$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
$*SPEC.rootdir;};'
#returns:
/Users/admin/logs
/Users/admin
/Users
/
Note, above won't actually check if the given directory is valid--it only
checks the parents. To check a given directory first, try the following:
~$ echo "/Users/admin/bogus_dir/" | raku -e 'for lines.IO -> $a is copy {if
$a.d {$a.Str.say; repeat {$a.=parent andthen $a.Str.say;} until $a eq
$*SPEC.rootdir}};'
#returns nothing for `bogus_dir`
HTH, Bill.
On Mon, Sep 5, 2022 at 1:56 PM Marc Chantreux wrote:
> I love this one. I used uniq and run so the whole script can be run from
> raku (except the xargs ls avoid the ARG_MAX error)
>
> <<. raku -e 'run < ls -lUd >, unique map {(.IO, *.parent …^
> "/")>>.Str.Slip}, lines'
> /var/log/messages
> /var/log/auth.log
>
> regards
>
> --
> Marc Chantreux
> Pôle de Calcul et Services Avancés à la Recherche (CESAR)
> http://annuaire.unistra.fr/p/20200
>
Re: steps of a path
On Wed, Sep 7, 2022 at 1:20 AM Marc Chantreux wrote: > > Actually what I really like the most from all your answers was the fact > that I learned a lot not only about the langage but also some idoms. That sounds cool. :) I know what *I* think of when I write "idiom" in the context of programming languages. But what do *you* mean? Or, even better, can you identify a few of the many useful suggestions folk have made in this thread which you would count as being, or possibly worthy of being, "idioms"? Wikipedia notes two uses of the term "idiom" in this context (claiming the first is correct but the second isn't, though the distinction seems immaterial here): > code [with a] semantic role, which recurs frequently across software projects > using a programming language in a typical way I know I wasn't particularly aiming at either of those, but instead playing golf in response to what I thought you were after, and focusing on: * First and foremost, Larry's notion of "clean golf" (minimal tokens, not bytes). * Secondarily my notion of "semantic golf" (minimal mental effort when reading). In other words my goal was code requiring minimal reading effort to understand while still appropriately expressing the desired computational result and/or effect. > > Is that because it knows me, or has google started blessing Larry's > > neologisms for the whole planet?!? ) I now think it (gmail and/or my brain; they may or may not have merged) glitched on me. > Why not? new words happens all the time and those one are useful for > programmers. I had done a google for "whipupitude" before I wrote the thought bubble in my previous message. Google claimed it found 300 results. I just tried again; adding -perl shrank their claim to just 8 matches. That said, right now gmail is claiming whipupitude is misspelled... -- raiph > > -- > Marc Chantreux > Pôle de Calcul et Services Avancés à la Recherche (CESAR) > http://annuaire.unistra.fr/p/20200
Re: steps of a path
Hi Ralph, > Given that the broader picture is file/path related operations, it makes > sense to me you're mostly exploring use of `.parent` and `map`s etc. Actually what I really like the most from all your answers was the fact that I learned a lot not only about the langage but also some idoms. > Is that because it knows me, or has google started blessing Larry's > neologisms for the whole planet?!? ) Why not? new words happens all the time and those one are useful for programmers. -- Marc Chantreux Pôle de Calcul et Services Avancés à la Recherche (CESAR) http://annuaire.unistra.fr/p/20200
Re: steps of a path
On Mon, Sep 5, 2022 at 8:07 AM Marc Chantreux wrote: > > I just played again with your solution and got the beauty of it. > > Actually: this is by far the simplest solution. Thanks. Thanks for the follow up. So I'm not going mad! :) Given that the broader picture is file/path related operations, it makes sense to me you're mostly exploring use of `.parent` and `map`s etc. Manipulexity is just as important as whipupitude! .oO ( gmail's spell checker corrected my spelling of whipupitude, letting me know that it considered whipuptitude (with an extra 't') misspelled. Is that because it knows me, or has google started blessing Larry's neologisms for the whole planet?!? ) That said, a big part of my focus was due to: > I thought the raku one could be shorter but for now I'm stuck with a very > long solution. and > I'm pretty sure I saw a very concise and elegant way to... Any help on that ? And when I see that kind of thing I tend to pop my "clean golf" mental hat on. So it was good to hear the lead commentator appreciate my swing at it. :) -- raiph
Re: steps of a path
I love this one. I used uniq and run so the whole script can be run from
raku (except the xargs ls avoid the ARG_MAX error)
<<. raku -e 'run < ls -lUd >, unique map {(.IO, *.parent …^ "/")>>.Str.Slip},
lines'
/var/log/messages
/var/log/auth.log
regards
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
Re: steps of a path
> On Sep 5, 2022, at 1:54 AM, Marc Chantreux wrote:
--snip of Bill's pointer to Mathew's email--
> I tried this line but got an immutability problem. I tried
> multiple work around with no success for the moment.
> <<. raku -e 'lines.IO.map: {repeat {.put} while not .=parent ~~ "/" }'
> /var/log/messages
--snip--
> On Sep 5, 2022, at 2:40 AM, Fernando Santagata
> wrote:
> you can get around the immutability problem:
> raku -e '"/var/log/messages".IO.map: -> $_ is copy {repeat {.put} while ! ($_
> .= parent ~~ "/") }'
--snip--
The use of `.parent` inspired me to think of this shorter solution, via the
Sequence Operator:
$ raku -e '.put for "/var/log/messages".IO, *.parent …^ "/";'
/var/log/messages
/var/log
/var
https://docs.raku.org/language/operators#infix_...
--
Hope this helps,
Bruce Gray (Util of PerlMonks)
Re: steps of a path
Hello,
you can get around the immutability problem:
raku -e '"/var/log/messages".IO.map: -> $_ is copy {repeat {.put} while !
($_ .= parent ~~ "/") }'
On Mon, Sep 5, 2022 at 8:55 AM Marc Chantreux wrote:
> hello William,
>
> On Sat, Sep 03, 2022 at 04:27:04PM -0700, William Michels wrote:
> > Hi Marc, There's also this conversation from March 2021 on the mailing
> list:
> > https://www.nntp.perl.org/group/perl.perl6.users/2021/03/msg9857.html
> > [Matthew's answer looks very interesting].
>
> Interesting as it can provide a relative short solution with no advanced
> concept. I tried this line but got an immutability problem. I tried
> multiple work around with no success for the moment.
>
> <<. raku -e 'lines.IO.map: {repeat {.put} while not .=parent ~~ "/" }'
> /var/log/messages
>
> thank you
>
> --
> Marc Chantreux
> Pôle de Calcul et Services Avancés à la Recherche (CESAR)
> http://annuaire.unistra.fr/p/20200
>
--
Fernando Santagata
Re: steps of a path
Hi Ralph,
> The `.Str.say` can be just `.put`.
oh! got it. thanks :)
> If not, can you see why I'm surprised -- why `m:g{ "/" <-[/]>+ }`
> seems simpler to me than `m:ex{^ [:r "/" <-[/]>+]+? }`?
I just played again with your solution and got the beauty of it. why
made me realize I should take time between two post so I can have a
fresh mindset for all of them!
Actually: this is by far the simplest solution. Thanks.
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
Re: steps of a path
hello William,
On Sat, Sep 03, 2022 at 04:27:04PM -0700, William Michels wrote:
> Hi Marc, There's also this conversation from March 2021 on the mailing list:
> https://www.nntp.perl.org/group/perl.perl6.users/2021/03/msg9857.html
> [Matthew's answer looks very interesting].
Interesting as it can provide a relative short solution with no advanced
concept. I tried this line but got an immutability problem. I tried
multiple work around with no success for the moment.
<<. raku -e 'lines.IO.map: {repeat {.put} while not .=parent ~~ "/" }'
/var/log/messages
thank you
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
Re: steps of a path
Marc Chantreux wrote:
>
> I got ([^1,^2,^3]) and tried to generalize it with something
> more generic (using * to get the number of elements).
Yeah, I was disappointed that that didn't work, and that what
did was relatively ugly, which is why I didn't bother to share it.
<<. raku -ne '.Str.say for m:ex{^ [:r "/" <-[/]>+]+? }'
The `.Str.say` can be just `.put`.
I'm surprised about your preference.
Is that because you're unfamiliar with Bruce's suggestion
(cumulative concat), or worry others will be unfamiliar with it?
If not, can you see why I'm surprised -- why `m:g{ "/" <-[/]>+ }`
seems simpler to me than `m:ex{^ [:r "/" <-[/]>+]+? }`?
--
raiph
Re: steps of a path
Hi Marc, There's also this conversation from March 2021 on the mailing list: https://www.nntp.perl.org/group/perl.perl6.users/2021/03/msg9857.html [Matthew's answer looks very interesting]. Anyway, HTH. --Bill. On Sat, Sep 3, 2022 at 2:51 PM Marc Chantreux wrote: > On Sat, Sep 03, 2022 at 09:50:08PM +0100, Ralph Mellor wrote: > > > ( A B C ) to ((A) (A B) (A B C)) ? > > [^1,^2,^3] > > I got that one and tried to generalize it with something more generic > (using * to get the number of elements). > > thanks for helping > > -- > Marc Chantreux > Pôle de Calcul et Services Avancés à la Recherche (CESAR) > http://annuaire.unistra.fr/p/20200 >
Re: steps of a path
On Sat, Sep 03, 2022 at 09:50:08PM +0100, Ralph Mellor wrote: > > ( A B C ) to ((A) (A B) (A B C)) ? > [^1,^2,^3] I got that one and tried to generalize it with something more generic (using * to get the number of elements). thanks for helping -- Marc Chantreux Pôle de Calcul et Services Avancés à la Recherche (CESAR) http://annuaire.unistra.fr/p/20200
Re: steps of a path
Hi Bruce and William,
Ineed: I was looking for [\,] but your code removes the anoying empty
string because of the leading / (which is awesome) so I mixed from both
answers (<-[/]> is more robust than .alpha ) and added .Str to .say.
finally I got:
<<. raku -ne '.Str.say for m:ex /^ ["/" <-[/]>+:] **? 1..* /;'
/var/log/messages
ther is only one caracter I don't understand in this anwser so I
considered removing it. bad idea:
<<. raku -ne '.Str.say for m:ex /^ ["/" <-[/]>+ ] **? 1..* /;'
/var/log/messages
so I read about backtracking and found something I found a bit easier
to get/memorize: the :r adverb.
<<. raku -ne '.Str.say for m:ex{ ^ [ :r "/" <-[/]>+ ] **? 1..* }'
/var/log/messages
last but not least: **? 1..* is just +?. At this point, my prefered solution
is:
<<. raku -ne '.Str.say for m:ex{^ [:r "/" <-[/]>+]+? }'
/var/log/messages
and it is pretty good compared to the sed version:
<<. sed -E ':b p; s:/[^/]+$::; t b'
thank you very much to both of you: I learned a lot on this post.
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
Re: steps of a path
On Sat, Sep 3, 2022 at 9:50 PM Ralph Mellor wrote:
>
> .put for [\~] '/A/B/C' ~~ m:g { '/'? <-[/]>+ }
That won't match just a slash (`/`). Maybe:
.put for [\~] '/A/B/C' ~~ m:g { ('/'? <-[/]>*) }
And it'll treat `/a/b` and `/a/b/` as distinct if the input string is `/a/b/`.
--
raiph
Re: steps of a path
On Sat, Sep 3, 2022 at 9:50 PM Ralph Mellor wrote: > > it makes more sense to do something like Bruce or Michel's solutions. s/Michel/William/ -- raiph
Re: steps of a path
On Sat, Sep 3, 2022 at 6:17 PM Marc Chantreux wrote:
>
> ( A B C ) to ((A) (A B) (A B C)) ?
[^1,^2,^3]
I could share a generalization but it's pretty ugly and I also think
it makes more sense to do something like Bruce or Michel's solutions.
Here's my variation:
.put for [\~] '/A/B/C' ~~ m:g { '/'? <-[/]>+ }
--
raiph
Re: steps of a path
Hi Marc (and Bruce)!
Okay, I use our old friend `:exhaustive` adverb below:
~$ echo "/var/log/messages" | raku -ne '.say for m:ex/ ^ ["/"
<.alpha>+:]**?{1..*} /;'
｢/var｣
｢/var/log｣
｢/var/log/messages｣
If you remove the `?` frugal quant-modifier, the output is the same--except
in the reverse order.
HTH, Bill.
On Sat, Sep 3, 2022 at 12:45 PM Bruce Gray wrote:
>
> > On Sep 3, 2022, at 12:17 PM, Marc Chantreux wrote:
>
> --snip--
>
> > I thought the raku one could be shorter
>
> It will be hard to beat the brevity of a language with single-character
> instructions.
>
> --snip--
>
> > I'm pretty sure I saw a very concise and elegant way to transform
> > ( A B C ) to ((A) (A B) (A B C))
>
> Perhaps you are remembering `produce()`, also called "triangular reduce":
> https://docs.raku.org/routine/produce
> https://docs.raku.org/language/operators#Reduction_metaoperators
>
> $ raku -e 'say [\,] ;'
> ((A) (A B) (A B C))
>
> $ echo /var/log/messages | raku -ne '.say for [\~] .comb: /\/<-[/]>+/;'
> /var
> /var/log
> /var/log/messages
>
> --
> Hope this helps,
> Bruce Gray (Util of PerlMonks)
>
>
Re: steps of a path
> On Sep 3, 2022, at 12:17 PM, Marc Chantreux wrote: --snip-- > I thought the raku one could be shorter It will be hard to beat the brevity of a language with single-character instructions. --snip-- > I'm pretty sure I saw a very concise and elegant way to transform > ( A B C ) to ((A) (A B) (A B C)) Perhaps you are remembering `produce()`, also called "triangular reduce": https://docs.raku.org/routine/produce https://docs.raku.org/language/operators#Reduction_metaoperators $ raku -e 'say [\,] ;' ((A) (A B) (A B C)) $ echo /var/log/messages | raku -ne '.say for [\~] .comb: /\/<-[/]>+/;' /var /var/log /var/log/messages -- Hope this helps, Bruce Gray (Util of PerlMonks)
steps of a path
hello people,
I have this steps() function implemented this way in shell:
steps() sed -r ':b p; s,/[^/]+$,,; t b'
# demo:
<<. steps | xargs ls -lUd
/var/log/messages
which shows
-rw-r- 1 root adm 464304 Sep 3 19:03 /var/log/messages
drwxr-xr-x 22 root root 4096 Sep 3 00:00 /var/log
drwxr-xr-x 14 root root 4096 Jun 19 2021 /var
for those who don't know sed that much, the perl equivalent is:
steps() perl -lpe 'do {print} while s,/[^/]+$,,'
I thought the raku one could be shorter but for now I'm stuck
with a very long solution.
my \path = [ "/var/log/messages" .split: "/" ];
.say for (^path).map( { path[0..$_].join: "/" } )[1..*];
I'm pretty sure I saw a very concise and elegant way to transform
( A B C ) to ((A) (A B) (A B C)) in the past but I'm enable to figure
out how. Any help on that ?
thanks by advance.
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
