On Mon, 2008-09-01 at 15:46 +0200, Paolo Gianrossi wrote:
> First of all thank you (and all the others ;) for answering
>
> This looks more hairy than I think it should...
>
> Since I think I omitted some constraints I have, let me try to explain
> my issue a tiny bit better.
>
> What I would like to do is the following. I have a text file which I
> slurp. Its contents are in $content.
>
> Now I want to ask the user for a regex (any regex) and highlight where
> (if) it matches.
>
> If I try to hard cable the whole thing, it works just fine:
>
> use strict;
> use warnings;
> use diagnostics;
>
> my $text="this is a random text. Please match random string.\nAnother
> random something.\n";
>
> while ($text =~ s/random/final/){ #here it is hard-coded
> my $l=length($`);
> print substr($text, 0, $l);
> print ">";
> print substr($text, $l);
> }
>
> This behaviour is just what I want. Only, I'd like to ask for the regexp
> to the user:
>
> use strict;
> use warnings;
> use diagnostics;
>
> my $text="this is a random text. Please match random string.\nAnother
> random something.\n";
>
> my $rexp=<STDIN>;
chomp( $rexp );
# I take it that you want $rexp to be
# of the form: s/random/final/
my $replacement = '';
if( $rexp =~ /^s(.)/ ){
my $delimiter = $1;
( undef, $rexp, $replacement ) = split /$delimiter/, $rexp;
}else{
die "badly formatted substitution: $rexp";
}
> while ($text =~ $rexp){ #here it isn't hardcoded anymore.
while( $text =~ s/$rexp/$replacement/g ){
> my $l=length($`);
> print substr($text, 0, $l);
> print ">";
> print substr($text, $l);
> }
>
> Of course this works not.
>
> Also, though,
>
> ...
> while (eval{$text =~ $rexp}){ # try to evaluate this, but not in the
> # proper way
> my $l=length($`);
> print substr($text, 0, $l);
> print ">";
> print substr($text, $l);
> }
>
> doesn't work. eval{$text =~ $rexp} is always undef. Now, this puzzles
> me, but whatever. My major point is that perldoc perlvar tells me that
> $` and friends are dynamically local to the eval block, so I am no game.
>
> Any clue about how to solve this?
>
> thanks a lot again for any help :)
> > Also see:
> >
> > perldoc -q "How can I expand variables in text strings?"
>
> oh btw, didn't know about -q... That's something cool!
`perldoc -q` searches only the FAQ. See http://perldoc.perl.org/ for
search engine that searches all of the perldoc's. Make sure it is
searching the correct version; to see what version of Perl you are
running, enter:
perl -v
--
Just my 0.00000002 million dollars worth,
Shawn
"Where there's duct tape, there's hope."
Cross Time Cafe
"Perl is the duct tape of the Internet."
Hassan Schroeder, Sun's first webmaster
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
http://learn.perl.org/
