Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

this is a basic, apprentice level question, but:
am processing a bunch of xhtml files to wml format and i want to find out how i can get the value of a pattern into a variable and then interpolate this variable where needed.
files i'm processing appear thus:
 <img src="xhtml/img/cancel.gif" width="24" height="13" alt="Cancel" /
+>
<textarea type="text" value="foo" name="text_message" />&nbsp;<%bar%>&
+nbsp;</p>

[download]
what i want to do, and can't, is cut  /<%bar%>/and put it into /foo/ while replacing /textarea/ with /input/
here's where i've got to:

foreach $file (@files) {
    $file_new = $file;
           open(IN, $file_new);
      
    $content = <IN>;
    
    $content =~s/xhtml/wml/g;
    #...do lots more swopping here...

    $content =~s/<h1>/<p><b>/g;

    # now i want to replace /textarea/ below with /input/ and also tak
+e /<%bar%>/ and put it into /foo/
    # trying something like this- doesn't work 

    while ($content =~ m/\(<textarea.*?>\)/sg) {
        my $match = $1; $match =~ s/\n//g;
        print " MATCH   $match\n";
    
    
        if($bar=~m/<%*?%>/){
        $foo =~ m/foo/;
        $value_of_bar = $bar;
        # how to get $bar into $foo?
        $content =~ s/$foo/$bar/g;
        }
    }

# write $content to file
open(OUT, ">$ARGV[1]/$file_new") || die "cannot open $ARGV[1]/$file_ne
+w";
    print $content;
    print OUT $content;

[download]
many thanks!

Replies are listed 'Best First'.
Re: extracting regex into, and interpolating, variable
by roik (Scribe) on Oct 23, 2002 at 13:57 UTC
    I think the following aproach will achieve the string replacement you are looking for though you might want to refine it. I am assuming for example that there will always be a %bar% on a line with <textarea!
    use strict;

my $line = qq(<textarea type="text" value="foo" name="text_message" />
+&nbsp;<%bar%>&nbsp;</p>);
my $foo = "foo";

if ($line =~ /<textarea .+<(%.+%)>/) {
    my $bar = $1;
    $line =~ s/<textarea/<input/;
    $line =~ s/$bar/$foo/;
    print $line;
}

exit;

    [download]
[reply]
[d/l]
      Hi, the initial post was mine, I posted anonymously by mistake.
      Thanks for the tip. The problem is that I can't guarantee the value of "foo" or indeed the attributes of "textarea", so I have to do some kind of pattern match like m/\(<textarea.*?>\)/ and then do a match on that to get the value of "value", if that makes sense.
      then, I need to insert all this into the variable that contains the whole file i.e. $content
      thanks,
      z.
[reply]
[d/l]
[select]
        Hi, having read your post a little more carefully, I think maybe this is a bit closer to what you want. $1 holds the match after "value=".
        use strict;

my $line = qq(<textarea type="text" value="foo" name="text_message" />
+&nbsp;<%bar%>&nbsp;</p>);

if ($line =~ /<textarea .+ value="(.+?)".+(<%.+%>)/) {

    my $foo = $1;
    my $bar = $2;
    $line =~ s/<textarea/<input/;
    $line =~ s/$bar/$foo/;
    print $line;
    
}

        [download]
[reply]
[d/l]

Back to Seekers of Perl Wisdom