my @array = qw/ element1 element2 element3 /;

##</code><code>##

my @array = ();
push @array, 'element1';
push @array, 'element2';
push @array, 'element3';

##</code><code>##

my $pattern = join '|', @final_array;

##</code><code>##

s/pattern1|pattern2|pattern3/replace/g;

# which is equivalent to
my $patterns = "pattern1|pattern2|pattern3";
s/$patterns/replace/g;