>Boring hard-to-read solution not using any of those
> raku -e'.say for sort grep *.starts-with(q[WARN]),lines' sample.log
Interesting! I don't think I've seen a comma used like that in a
one-liner. Also a very fast solution (thanks Brad!).
Presumably the ",lines" tells raku/perl6 to run the preceding code on
input lines?
TIA, Bill.
On Fri, May 8, 2020 at 11:03 AM yary <not....@gmail.com> wrote:
>
> > perl6 -e 'lines() ==> grep /^WARN/ ==> sort() ==> join("\n") ==> say();'
>
> that's neat too.
>
> This is showed me that I didn't have a clear grasp of the feed operator ==>
> vs the hyper-operator >>
>
> Now I have learned/internalized that the feed operators pass along the entire
> sequence (list?), whereas the hyper-operator passes items one at a time.
> Hence "==> say" putting the results on one line, because "say" is getting the
> entire list. And ">>.sort" not sorting, because sort would be called once
> per item with only that single item to sort.
>
> Boring hard-to-read solution not using any of those
>
> raku -e'.say for sort grep *.starts-with(q[WARN]),lines' sample.log
>
> -y
>
> On Fri, May 8, 2020 at 1:20 PM William Michels <w...@caa.columbia.edu> wrote:
>>
>> Maybe?
>>
>> perl6 -e 'lines() ==> grep /^WARN/ ==> sort() ==> join("\n") ==> say();'
>>
>> HTH, Bill.
>>
>>
>> On Fri, May 8, 2020 at 9:10 AM Fernando Santagata
>> <nando.santag...@gmail.com> wrote:
>> >
>> > raku -e'.say for lines() ==> grep(/^WARN/) ==> sort' sample.log
>> >
>> > is not very satisfying because for the "for" which breaks the flow.
>> > OTOH this
>> >
>> > raku -e'lines().grep(/^WARN/).sort».say' sample.log
>> >
>> > doesn't use the feed operator and this
>> >
>> > raku -e'lines() ==> grep(/^WARN/) ==> sort() ==> say()' sample.log
>> >
>> > outputs a list on one line, not each line on its own. This one works, but
>> > it feels awkward:
>> >
>> > raku -e'lines() ==> grep(/^WARN/) ==> sort() ==> reduce({$^a ~ "\n" ~
>> > $^b}) ==> say()' sample.log
>> >
>> > On Fri, May 8, 2020 at 5:49 PM yary <not....@gmail.com> wrote:
>> >>
>> >> All good ideas so far, in the "more than one way to do it" spirit, can
>> >> use "state" instead of "my", since state only initializes 1st time it's
>> >> hit.
>> >>
>> >> raku -ne 'state @i;@i.push($_) if .starts-with(q[WARN]); END .say for
>> >> @i.sort' sample.log
>> >>
>> >> Or adapting Brad's answer with the feed operator for fun
>> >>
>> >> raku -e 'for lines() ==> grep /^WARN/ ==> sort() {.say}' sample.log
>> >>
>> >> Now, I didn't want to use 'map' in there, because of a habit of only
>> >> using 'map' when I want the return values. When looping for side-effects
>> >> only, like saying each value in a list, I want to use 'for'.
>> >> UnFORtunately though I cannot find anything as clean looking as
>> >>
>> >> raku -e 'lines() ==> grep /^WARN/ ==> sort() ==> map *.say' sample.log
>> >>
>> >> reading entirely L-to-R which does NOT use map... ideas?
>> >>
>> >> -y
>> >>
>> >>
>> >> On Fri, May 8, 2020 at 10:10 AM William Michels via perl6-users
>> >> <perl6-us...@perl.org> wrote:
>> >> >
>> >> > On Fri, May 8, 2020 at 5:16 AM WFB <wolfgang.banas...@gmail.com> wrote:
>> >> > >
>> >> > > Hi,
>> >> > >
>> >> > > I am trying to write an one-liner to go through all lines in a
>> >> > > logfile and look for an certain key word, store the line and sort
>> >> > > them before printing them out.
>> >> > >
>> >> > > My approach was:
>> >> > > raku -ne "BEGIN {my @i }; @i.push($_); if $_ ~~ /^WARN/; END {
>> >> > > @i.sort.say }"
>> >> > > That does not work because @i does not exist in the if clause. I
>> >> > > tried our @i as well with no luck.
>> >> > >
>> >> > > How can I store data that can be accessed in the END phaser? Or is
>> >> > > there another way to archive it? TIMTOWTDI^^
>> >> > >
>> >> > > One hint I found was the variable $ and @ respectively. But those
>> >> > > variables are created for each line new...
>> >> > >
>> >> > >
>> >> > > I did not found a help or examples for -npe except raku -h. Is there
>> >> > > more helpful stuff somewhere in doc.raku.org? If so I could'nt find
>> >> > > it.
>> >> > >
>> >> > > Thanks,
>> >> > > Wolfgang
>> >> >
>> >> > Hi Wolfgang,
>> >> >
>> >> > This is a first attempt at doing what you want: I'm sure it can be
>> >> > shortened. Since one of your requirements is doing a sort on filtered
>> >> > values stored in an array, I abandoned use of the "-ne" one-liner
>> >> > flag, using "-e" and "for lines()" instead. I also used grep instead
>> >> > of smart-matching:
>> >> >
>> >> > perl6 -e 'my @i; for lines() {if .grep(/^WARN/) -> ($s)
>> >> > {@i.push($s)};}; .say for @i.sort;'
>> >> >
>> >> > Note: the "-> ($s)" section where I store grepped matches comes from a
>> >> > Jonathan Worthington answer found here (thanks Jonathan!):
>> >> >
>> >> > stackoverflow.com/questions/58982745/raku-one-line-expression-to-capture-group-from-string
>> >> >
>> >> > I certainly would be interested to learn if there's a phaser solution
>> >> > to this problem (and I also have a sneaking suspicion that Supply
>> >> > might be useful here... ).
>> >> >
>> >> > HTH, Bill.
>> >
>> >
>> >
>> > --
>> > Fernando Santagata
