Strip out the bit you want and put it in a hash. Then put the decoration back when you use it. 

#! perl -slw
use strict;

my %filters;
@filters{ ( split ',' )[1] =~ m[//\*\.([^*]+)\*] } = 1
    while <DATA> ;

printf "http://*.%s*/*\n", $_ for keys %filters;

=output
C:\test>826863
http://*.google.com*/*
http://*.gmail.com*/*
http://*.yahoo.com*/*
=cut


__DATA__
parm1,http://*.google.com*/*,parm3
parm1,http://*.google.com*/*,parm3
parm1,http://*.yahoo.com*/*,parm3
parm1,http://*.google.com*/*,parm3
parm1,http://*.gmail.com*/*,parm3
parm1,http://*.yahoo.com*/*,parm3
parm1,http://*.google.com*/*,parm3

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"I'd rather go naked than blow up my ass"

In reply to Re: ensuring unique elements in a list by BrowserUk
in thread ensuring unique elements in a list by repudi8or

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