>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-users@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