in reply to Re: Re: Efficiency issues in text parsing
in thread replacing text in specific tags

Hi, Thanks for your comments. One more small doubt i have.

here is the input data 

<input>
This is to test. this is to test
<p>This is to test. This is
to test</p>
<p>This is to test. This is
to test</p>
This is to test.
this is to test
</input>

[download]
<output>
This is to test. this is to test
<p>This is to test. This is to test</p>
<p>This is to test. This is to test</p>
This is to test.
this is to test
</output>

[download]
i.e. i want to make the <p>...</p> as single line. i mean delete the carrage returns only inside <p>...</p> my following code does the job, but only for the last <p>...</p>. i don't know how to loop it here. pls suggest 
$infile = $ARGV[0];

open(IN, '<', "temp.in") || die "\nCan't open temp.in \n";
open(OUT, '>' "temp.out");
$/="";
while(<IN>)
{
    if($_=~s/(.*)&lt;p&gt;(.*)\<\/p\>(.*)//ms)
    {
        $pre =  $1;
        $par =  $2;
        $pos =  $3;

        $par=~s#\n# #ig;
        print OUT "$pre&lt;p&gt;$par\<\/p\>$pos";
    }
}
close(IN);
close(OUT);

[download]
Note: also please let me know how to include the source code in this page, any special tags for that? i mean the code formatting is often getting messed when i post

edited by ybiC: Reformatted to avoid lateral scrolling in browser window - balanced <code>tags around example input+output and code

Replies are listed 'Best First'.
Re: Re: Efficiency issues in text parsing
by CombatSquirrel (Hermit) on Aug 27, 2003 at 01:04 UTC
    Have a look at Writeup Formatting Tips.
    To your problem: The following program did the trick for me: 
    #!perl

use strict;
use warnings;

{ # braces for localization of $/
   local $/ = '<p>'; # end of record is now <p>
   print scalar <DATA>; 
      # first chunk contains everything before first <p> tag, just pri
+nt
   for (<DATA>) {
      s@([\d\D]*?</p>)@ my $var = $1; $var =~ s!\n! !g; $var @e; 
         # substitute newlines by spaces before the closing </p> tag
      print;
   }
}
__DATA__
This is to test. this is to test
<p>This is to test. This is
to test</p>
<p>This is to test. This is
to test</p>
This is to test.
this is to test

    [download]
    Hope this helped.
    CombatSquirrel.
    Entropy is the tendency of everything going to hell.
[reply]
[d/l]
      Your code does the magic. Thanks you very much

      but one small doubt: what does "$var @e;" mean, particularly "@e", what does it mean here.

      can you please suggest me some good perl book to handle this kind of stuffs.

      once again, thanks a lot

[reply]
        The "@" is just the seperator for the RegEx which starts with "s@". The "e" is a modifier that specifies that the substitution part should be evaluated and the result be taken as the real substitute. And since the last line is always the return value, I just put $var as the last value, because it contains the substitue.
        Cheers,
        CombatSquirrel.
        Entropy is the tendency of everything going to hell.
[reply]

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