my $filename = shift;

if ($line = /something/) {
}

foreach (@arr) {
   if (/abc/) {
      print;
   }
}

sub foo {
   my $x = shift;
}

##</code><code>##

my $filename = shift @ARGV;

if ($line = $_ =~ /something/) {
}

foreach $_ (@arr) {
   if ($_ =~ /abc/) {
      print $_;
   }
}


sub foo {
   my $x = shift @_;
}