My guesses at Perl 6 versions of the Perl 5 example:

   say .split(':')[0, 2, 1, 5].join("\t") for lines;

-or-

   for lines { say .split(':')[0, 2, 1, 5].join("\t") }

Pm


On Mon, Jul 29, 2019 at 12:49:51PM -0700, William Michels via perl6-users wrote:
> Hello, Just a short backgrounder to say that this question arose this
> past weekend at a Perl6 Meetup (Oakland, CA). Specifically we were
> looking at how to write a Perl6 version of some introductory Perl5
> code in "Learning Perl", 7th Edition by Tom Phoenix, brian d foy,
> Randal L. Schwartz:
> 
> #Perl 5 code below:
> while (<>) {
>   chomp;
>   print join("\t", (split /:/)[0, 2, 1, 5] ), "\n";
> }
> 
> https://www.oreilly.com/library/view/learning-perl-7th/9781491954317/ch01.html
> 
> (Thanks to Joseph Brenner for organizing the Perl6 Meetup).
> 
> 
> 
> 
> 
> 
> On Mon, Jul 29, 2019 at 2:09 AM Elizabeth Mattijsen <l...@dijkmat.nl> wrote:
> >
> > Also, you can make this conditional:  show me all the comment lines of a 
> > source file:
> >
> >
> > $ perl6 -e '.say if .starts-with('#') for lines' source-file
> >
> >
> > > On 29 Jul 2019, at 10:06, Richard Hainsworth <rnhainswo...@gmail.com> 
> > > wrote:
> > >
> > > Also no need for all the brackets
> > >
> > > .say for lines;
> > >
> > > This is quite idiomatic Perl 6 and not golfing
> > >
> > > On Mon, 29 Jul 2019, 07:13 Joseph Brenner, <doom...@gmail.com> wrote:
> > > > Hmmm. I would expect that to be in the Perl 5 to Perl 6 Migration 
> > > > Guides, but I do not see it there.
> > >
> > > Exactly, I was just looking there, and I ended up playing around with
> > > the method form of lines, and didn't think to try the function
> > > form of it.
> > >
> > > To summarize, if the goal is to write a "simple_echo" script that
> > > can work with a file name or with lines on standard input:
> > >
> > >    simple_echo lines.txt
> > >    cat lines.txt | simple_echo
> > >
> > > The perl5 version would probably be:
> > >
> > >   #!/usr/bin/env perl
> > >   while(<>){
> > >      print;
> > >   }
> > >
> > > The perl6 version would be something like:
> > >
> > >   #!/usr/bin/env perl6
> > >   use v6;
> > >   for lines() {
> > >       say $_;
> > >   }
> > >
> > >
> > > The kind of thing I was playing with was:
> > >
> > >   #!/usr/bin/env perl6
> > >   use v6;
> > >   my @lines = $*ARGFILES.IO.lines;
> > >   say @lines;
> > >
> > > That works for lines from a file, but not from standard input, and  the
> > > error message isn't tremendously helpful:
> > >
> > >   No such method 'lines' for invocant of type 'IO::Special'
> > >
> > >
> > >
> > >
> > > On 7/28/19, Bruce Gray <robertbrucegr...@gmail.com> wrote:
> > > >
> > > >
> > > >> On Jul 28, 2019, at 6:20 PM, Joseph Brenner <doom...@gmail.com> wrote:
> > > >>
> > > >> I was just wondering if there's some direct analog in perl6 to the
> > > >> perl5 construct:
> > > >>
> > > >>  while(<>){ ... }
> > > >>
> > > >> If I'm planning on passing a filename on the command-line, I can just
> > > >> get it out of $*ARGFILES easily enough, but what if I also wanted it
> > > >> to work on lines passed in via standard input?
> > > >
> > > >
> > > > `lines` , as a sub instead of a method, and no arguments.
> > > >
> > > > See: https://docs.perl6.org/routine/lines#(Cool)_routine_lines
> > > >       Without any arguments, sub lines operates on $*ARGFILES, which 
> > > > defaults to
> > > > $*IN in the absence of any filenames.
> > > >
> > > > For example:
> > > >       perl6 -e 'say .join("\t") for lines().rotor(4);' path/to/file.txt
> > > >
> > > > Hmmm. I would expect that to be in the Perl 5 to Perl 6 Migration 
> > > > Guides,
> > > > but I do not see it there.
> > > >
> > > > —
> > > > Hope this helps,
> > > > Bruce Gray (Util of PerlMonks)
> > > >
> > > >

Reply via email to