sub f {
  $_++ for @_;
}

use FileHandle;
sub angle {
  my $fh = FileHandle->new(q(echo hi |)) or die "$cmd failed\:$!";
  while (<$fh>) {}; #nop
}

$_ = 1;
@a = qw(0 1 2);

local $" = ':';
print "original values:\n";
print "\t\$_=>$_\n";
print "\t\@a=>@a\n";
f @a;
print "for has modified \@a, using a localized \$_\n";
print "\t\$_=>$_\n";
print "\t\@a=>@a\n";
angle;
print "angle has modified a non-localized \$_\n";
print "\t\$_=>$_\n";