# odd way to count lines of a file :-)
use strict;
use warnings;

use IO::Handle;
my $fh = IO::Handle->new; #good
# $fh = do {local *FH};   #bad
open ($fh, './test') or die("open failed: $!");
1 while <$fh>;
print "line: " . $fh->input_line_number();

__END__
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$. has its drawbacks - it contains the line number of last filehandle accessed. So there's no safe evaluation at a distance.

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                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}