"$lines = @{[ (<$file>) ]}".The problem is that the former doesn't work, and the latter gives $lines = 1.
Your 2nd example gives me the correct number of lines (not 1): 
use warnings;
use strict;
open my $file, '<', $0;
my $lines = @{[ (<$file>) ]};
print "$lines\n";

[download]

The output for me is 5.

In reply to Re: Forcing array context on a file handle by toolic
in thread Forcing array context on a file handle by ronmrdechai

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