The two ways I understand your question:

First, you want to known what elements from @pcov match with at least one pattern from @realassert.

Second, you want to know what elements from @pcov match with all patterns from @realassert

my @pcov = ('foobar','bilbao','bobo');
my @realassert = map {quotemeta} ('foo','ba');

my $re_one = join '|',@realassert;
#print $re_one;

my @result_one = grep { /$re_one/ } @pcov;
print "one: @result_one\n";

my @result_all = grep {
    my $item = $_;
    ! grep { $item !~ /$_/ } @realassert;
} @pcov;

print "all: @result_all\n";
__END__
one: foobar bilbao
all: foobar
[download]

edit: You could also look at http://perldoc.perl.org/perlop.html#Smartmatch-Operator

edit2: typo