comment on

#1 is buggy. A file name "0" will incorrectly die. The (not so pretty) solution:

defined(my $infile  = shift) || die usage();
defined(my $outfile = shift) || die usage();
[download]

I find #2's unless (@ARGV == 2) harder to read than if (@ARGV != 2).
I'd print usage to STDERR, so I prefer die("message"), warn("message") and print STDERR ("message") over #1 and #2's print("message").

In reply to Re: Best practices for processing @ARGV ? by ikegami
in thread Best practices for processing @ARGV ? by gu

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