rotor in comb?
hello people,
Here is a little raku code to count all the digraphs from some text:
my %digraphs =
slurp.lc
.comb(/<[a..z]>+/)
.map( *.comb.rotor( 2 => -1, :!partial ).map: *.join )
.Bag;
The first .comb match words then I map them to get digraphs but I think
it is possible to move the cursor backward in the comb regex. I just
don't know how. I'm trying to write something like:
slurp.lc
.comb(/ <[a..z]> ** 2 { --pos } /)
.Bag;
The perl version of it is:
perl -lnE '
END { say "$_ = $digraph{$_}" for
sort { $digraph{$b} <=> $digraph{$a} }
keys %digraph
}
$_=lc; while (/([a-z]{2})/g) {++$digraph{$1}; --pos; }
'
Any help is very welcome.
regards,
--
Marc Chantreux
Pôle de Calcul et Services Avancés à la Recherche (CESAR)
http://annuaire.unistra.fr/p/20200
Re: rotor in comb?
> On Aug 27, 2022, at 10:56 AM, Marc Chantreux wrote:
--snip--
> but I think it is possible to move the cursor backward in the comb regex.
--snip--
I do *not* think you can ("move the cursor backward in the comb regex"); See
https://docs.raku.org/routine/comb :
... "returns a Seq of non-overlapping matches" ...
The "non-overlapping" nature is the problem.
(Please let me know if this turns out to be incorrect!)
In foresight, Raku has added an optional `:exhaustive` flag to regex matching,
and that will do what you want.
This Raku code:
my %digraphs = slurp.lc.match(:exhaustive, /(<[a..z]> ** 2)/)».Str.Bag;
.say for %digraphs.sort({ -.value, ~.key });
, produces output identical to this Perl code:
perl -lnE '
END { say "$_ => $digraph{$_}" for
sort { $digraph{$b} <=> $digraph{$a} || $a cmp $b }
keys %digraph
}
$_=lc; while (/([a-z]{2})/g) {++$digraph{$1}; --pos; }
' Camelia.svg
, when run against a downloaded copy of our mascot:
https://upload.wikimedia.org/wikipedia/commons/8/85/Camelia.svg
--
Hope this helps,
Bruce Gray (Util of PerlMonks)
Re: rotor in comb?
Hi Marc (and Bruce)!
I'm adapting a "word frequency" answer posted by Sean McAfee on this list.
The key seems to be adding the `:exhaustive` adverb to the `match` call.
AFAIK comb will not accept this adverb, so `match will have to do for now:
Sample Input (including quotes): “A horse, a horse, my kingdom for a
horse!”
~$ raku -e '++(my %digraphs){$_} for slurp.lc.match(:global, :exhaustive,
/<[a..z]>**2/); .say for %digraphs.sort(-*.value);'
Sample Output:
or1 => 4
se1 => 3
rs1 => 3
ho1 => 3
in1 => 1
my1 => 1
om1 => 1
ki1 => 1
ng1 => 1
do1 => 1
gd1 => 1
fo1 => 1
HTH, Bill.
On Sat, Aug 27, 2022 at 10:25 AM Bruce Gray wrote:
>
>
> > On Aug 27, 2022, at 10:56 AM, Marc Chantreux wrote:
>
> --snip--
>
> > but I think it is possible to move the cursor backward in the comb regex.
>
> --snip--
>
> I do *not* think you can ("move the cursor backward in the comb regex");
> See https://docs.raku.org/routine/comb :
> ... "returns a Seq of non-overlapping matches" ...
> The "non-overlapping" nature is the problem.
> (Please let me know if this turns out to be incorrect!)
>
> In foresight, Raku has added an optional `:exhaustive` flag to regex
> matching, and that will do what you want.
> This Raku code:
>
> my %digraphs = slurp.lc.match(:exhaustive, /(<[a..z]> **
> 2)/)».Str.Bag;
> .say for %digraphs.sort({ -.value, ~.key });
>
> , produces output identical to this Perl code:
>
> perl -lnE '
> END { say "$_ => $digraph{$_}" for
> sort { $digraph{$b} <=> $digraph{$a} || $a cmp $b }
> keys %digraph
> }
> $_=lc; while (/([a-z]{2})/g) {++$digraph{$1}; --pos; }
> ' Camelia.svg
>
> , when run against a downloaded copy of our mascot:
> https://upload.wikimedia.org/wikipedia/commons/8/85/Camelia.svg
>
> --
> Hope this helps,
> Bruce Gray (Util of PerlMonks)
>
>
Re: rotor in comb?
Heads-up: code was correct in my last post, but the output is as follows
(Rakudo v2021.06):
~$ raku -e '++(my %digraphs){$_} for slurp.lc.match(:global, :exhaustive,
/<[a..z]>**2/); .say for %digraphs.sort(-*.value);' richard3.txt
or => 4
rs => 3
ho => 3
se => 3
gd => 1
in => 1
fo => 1
om => 1
do => 1
ng => 1
ki => 1
my => 1
On Sat, Aug 27, 2022 at 10:45 AM William Michels
wrote:
> Hi Marc (and Bruce)!
>
> I'm adapting a "word frequency" answer posted by Sean McAfee on this list.
> The key seems to be adding the `:exhaustive` adverb to the `match` call.
> AFAIK comb will not accept this adverb, so `match will have to do for now:
>
> Sample Input (including quotes): “A horse, a horse, my kingdom for a
> horse!”
>
> ~$ raku -e '++(my %digraphs){$_} for slurp.lc.match(:global, :exhaustive,
> /<[a..z]>**2/); .say for %digraphs.sort(-*.value);'
>
> Sample Output:
>
> or1 => 4
> se1 => 3
> rs1 => 3
> ho1 => 3
> in1 => 1
> my1 => 1
> om1 => 1
> ki1 => 1
> ng1 => 1
> do1 => 1
> gd1 => 1
> fo1 => 1
>
> HTH, Bill.
>
>
> On Sat, Aug 27, 2022 at 10:25 AM Bruce Gray wrote:
>
>>
>>
>> > On Aug 27, 2022, at 10:56 AM, Marc Chantreux wrote:
>>
>> --snip--
>>
>> > but I think it is possible to move the cursor backward in the comb
>> regex.
>>
>> --snip--
>>
>> I do *not* think you can ("move the cursor backward in the comb regex");
>> See https://docs.raku.org/routine/comb :
>> ... "returns a Seq of non-overlapping matches" ...
>> The "non-overlapping" nature is the problem.
>> (Please let me know if this turns out to be incorrect!)
>>
>> In foresight, Raku has added an optional `:exhaustive` flag to regex
>> matching, and that will do what you want.
>> This Raku code:
>>
>> my %digraphs = slurp.lc.match(:exhaustive, /(<[a..z]> **
>> 2)/)».Str.Bag;
>> .say for %digraphs.sort({ -.value, ~.key });
>>
>> , produces output identical to this Perl code:
>>
>> perl -lnE '
>> END { say "$_ => $digraph{$_}" for
>> sort { $digraph{$b} <=> $digraph{$a} || $a cmp $b }
>> keys %digraph
>> }
>> $_=lc; while (/([a-z]{2})/g) {++$digraph{$1}; --pos; }
>> ' Camelia.svg
>>
>> , when run against a downloaded copy of our mascot:
>> https://upload.wikimedia.org/wikipedia/commons/8/85/Camelia.svg
>>
>> --
>> Hope this helps,
>> Bruce Gray (Util of PerlMonks)
>>
>>
Re: Inconsistencies with "with" chained to "for"
Looks like it worth a bug report. I was probably stumbling upon this too for a couple of times. Best regards, Vadim Belman > On Aug 27, 2022, at 2:24 AM, Fernando Santagata > wrote: > > Hello, > I noticed this behavior: > > [0] > my @a = > [a b c d e] > [1] > .say with $_ for @a > () > [2] > .say if .defined for @a > a > b > c > d > e > [3] > (.say with $_) for @a > a > b > c > d > e > [4] > (.say if .defined) for @a > a > b > c > d > e > > Apparently in this case "with" works only as a statement modifier while "if" > works both ways. > Is this a known behavior with well understood reasons, or should I open an > issue? > > -- > Fernando Santagata
