The following subroutine seems to return the same result as yours, and is about 2 times faster. You didn't provide much testing data, so I'm not sure it will work correctly for the real input.

sub not_so_special {
    my $s = shift;
    my @cols = split /;/, $s, -1;
    my $e;
    $cols[2] =~ s/=(.+)/'=' . (' ' x length($e = $1))/e;
    return join ';', @cols, $e
}
[download]

Update
Or, maybe, more readable and a tiny bit faster:

sub new {
    my @cols = split /;/, shift, -1;
    $cols[2] =~ s/=(.+)/=/;
    $cols[2] .= ' ' x length $1;
    return join ';', @cols, $1
}
[download]

Update 2
This seems even faster (but uglier):

use Syntax::Construct qw{ /r };
sub newer {
    shift =~ s/^([^;]*;[^;]*;)(.*?=)([^;]*)(;.*)/"$1$2" . (' ' x lengt
+h $3) . "$4;$3"/er
}
[download]

---

---

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.