foreach(@file){
    open(my $fh, "<", "$file") or die "Could not open $file because $!\n";
    my @data = <$fh>;
    close($fh);
}
#memory used for @data gets garbage collected here

##</code><code>##

{
    my @data;
    foreach(@file){
        open(my $fh, "<", "$file") or die "Could not open $file because $!\n";
       @data = <$fh>;
       close($fh);
    }
}