It is possible to achieve using m//g.

my $line = 'This line has a hit here and a hit there.';
my $word = 'hit';

my $count = 0;
my $hilit = '';
while ($line =~ /(.*?)(?:\b($word)\b|\z)/sgi) {
   $hilit .= $1;
   if (defined($2)) {
      ++$count;
      $hilit .= "[$2]";
   }
}

print "$hilit\n";
print "$count occurrences of $word\n";
[download]

/c would indeed allow you to simplify the above.

my $line = 'This line has a hit here and a hit there.';
my $word = 'hit';

my $count = 0;
my $hilit = '';
while ($line =~ /(.*?)\b($word)\b/sgci) {
   $hilit .= "$1[$2]";
   ++$count;
}
$hilit .= substr($line, pos($line));

print "$hilit\n";
print "$count occurrences of $word\n";
[download]

But s///g is much simpler.

my $line = 'This line has a hit here and a hit there.';
my $word = 'hit';

my $count = (my $hilit = $line) =~ s/\b($word)\b/[$1]/gi;

print "$hilit\n";
print "$count occurrences of $word\n";
[download]

Note that if $word can contain characters other than those matched by \w, \b may fail and the contents may be treated as a regex instructions (e.g. $word="foo.bar" would match foolbar).

Update: Fixed a bug in first snippet.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.