my @subfoos = grep{m/$var/} @foos;

##</code><code>##

 
my $regvar  = $var; $regsol =~ s/\./___/g;
my @subfoos = map {s/___/\./g; $_} 
              grep{m/$regsol/} 
              map{s/\./___/g; $_}@foos;
}