[lug] Perl question: how to print embedded metacharacters

[Chip Atkinson]

Ha ha!  Thanks! :-D  Yeah, I have yet to see even mention of doing such a
thing on the web.

On Wed, 25 Nov 2009, Jeffrey Haemer wrote:

> Chip,
> 
> Yep, I'm using the shell to do the dirty work.
> 
> I don't doubt there are elegant, pure-Perl solutions.  I was only trying to
> find something that would work for you, immediately, until someone else
> volunteers a more PC (Perlishly Correct) way. :-)
> 
> On Wed, Nov 25, 2009 at 9:34 AM, Chip Atkinson <chip at pupman.com> wrote:
> 
> > Hmmmm... that does work, but isn't it using the bash printf rather than
> > perl?  My concern is how fast it would be.  I can experiment there though,
> > and it does work.
> >
> > Thanks for your help!
> >
> > Chip
> >
> > On Wed, 25 Nov 2009, Jeffrey Haemer wrote:
> >
> > > Chip,
> > >
> > > Okay.  Would something like this be good enough?
> > >
> > >
> > > #!/usr/bin/perl
> > >
> > > while (<>) {
> > >   $_=` printf "$_" `;
> > >   print;
> > > }
> > >
> > >
> > >
> > >
> > > On Wed, Nov 25, 2009 at 9:06 AM, Chip Atkinson <chip at pupman.com> wrote:
> > >
> > > > No, unfortunately.
> > > >
> > > > The problem is that the script reads the string in from the command
> > file,
> > > > so I need to interpret the string before printing it.  Here's another
> > > > example:
> > > > ---------------------
> > > > chip at chip-desktop:~$ cat try2.pl
> > > > #!/usr/bin/perl
> > > >
> > > > #my $kw = 'abc\ndef';
> > > > #my $nv = "${\($kw)}";
> > > >
> > > > while (<>) {
> > > >  print "$_";
> > > > }
> > > > chip at chip-desktop:~$ echo 'abc\ndef' | ./try2.pl
> > > > abc\ndef
> > > > chip at chip-desktop:~$
> > > > ---------------------------------
> > > > In a sense, I need the opposite of quotemeta -- something that takes in
> > a
> > > > string and does the metacharacter replacements.
> > > >
> > > > I know that something like
> > > > while (<>) {
> > > >  s/\\n/\n/g;
> > > >  # etc. for all metacharacter sequences...
> > > >  print;
> > > > }
> > > >
> > > > would work but I wanted to avoid the "etc. for all metacharacter
> > > > sequences"
> > > >
> > > > Hopefully that's more understandable.
> > > >
> > > > Chip
> > > >
> > > > On Wed, 25 Nov 2009, Jeffrey Haemer wrote:
> > > >
> > > > > Chip,
> > > > >
> > > > > Can you do this instead?
> > > > >
> > > > > my $kw = "abc\ndef";
> > > > >
> > > > > If not, can you explain in enough detail that I can try again? :-)
> > > > >
> > > > > On Wed, Nov 25, 2009 at 8:29 AM, Chip Atkinson <chip at pupman.com>
> > wrote:
> > > > >
> > > > > > Greetings,
> > > > > >
> > > > > > I'm working on a perl script that reads strings from a
> > configuration
> > > > file
> > > > > > and prints them out.  What I'd like to be able to do is have any
> > > > embedded
> > > > > > metacharacters interpreted but I'd like to avoid doing the
> > > > substitutions
> > > > > > myself.
> > > > > >
> > > > > > For example, here is a little script to emulate the problem:
> > > > > >
> > > > > > #!/usr/bin/perl
> > > > > >
> > > > > > my $kw = 'abc\ndef';
> > > > > >
> > > > > > print "$kw";
> > > > > > ----------------------
> > > > > > the output is
> > > > > > abc\ndef
> > > > > >
> > > > > > What I want is
> > > > > > abc
> > > > > > def
> > > > > >
> > > > > > --------------
> > > > > > I tried to jfgi but no joy.
> > > > > >
> > > > > > Thanks in advance.
> > > > > >
> > > > > > Chip
> > > > > >
> > > > > > _______________________________________________
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> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Click to Call Me Now! --
> > > > > http://seejeffrun.blogspot.com/2009/09/call-me-now.html
> > > > >
> > > > > Jeffrey Haemer <jeffrey.haemer at gmail.com>
> > > > > 720-837-8908 [cell],  @goyishekop [twitter]
> > > > > http://www.youtube.com/user/goyishekop [vlog]
> > > > >
> > > >
> > > > _______________________________________________
> > > > Web Page:  http://lug.boulder.co.us
> > > > Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug
> > > > Join us on IRC: lug.boulder.co.us port=6667 channel=#hackingsociety
> > > >
> > >
> > >
> > >
> > > --
> > > Click to Call Me Now! --
> > > http://seejeffrun.blogspot.com/2009/09/call-me-now.html
> > >
> > > Jeffrey Haemer <jeffrey.haemer at gmail.com>
> > > 720-837-8908 [cell],  @goyishekop [twitter]
> > > http://www.youtube.com/user/goyishekop [vlog]
> > >
> >
> > _______________________________________________
> > Web Page:  http://lug.boulder.co.us
> > Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug
> > Join us on IRC: lug.boulder.co.us port=6667 channel=#hackingsociety
> >
> 
> 
> 
> -- 
> Click to Call Me Now! --
> http://seejeffrun.blogspot.com/2009/09/call-me-now.html
> 
> Jeffrey Haemer <jeffrey.haemer at gmail.com>
> 720-837-8908 [cell],  @goyishekop [twitter]
> http://www.youtube.com/user/goyishekop [vlog]
>