I would write:

use warnings;
my $var=1;
print $var;

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Why the test? If $var is undef something much more serious is going on and I want to know about it.

Yes, I know this is a trivial example and you imply that there may be legitimate situations in which $var is undef. However I'm suggesting that if $var is undef when you are about to print its contents, then there is a flaw in the code. It may be as trivial as not having provided a default value, but providing the default value is important - it says to the reader that you have thought about the special case of the variable contents haven't been changed.

BTW, your second version is needlessly convoluted and will generate a warning (two if $var is undefined). KISS

DWIM is Perl's answer to Gödel

In reply to Re^2: Breaking The Rules by GrandFather
in thread Breaking The Rules by Limbic~Region

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