It is often annoying, though in some cases is does help find bugs.

I don't like introducing "if defined" checks, as they blow up the code size and make it less readable. Luckily the // operator provides a slightly more concise solution that can be use in many (but not all!) situations where you want to do string-comparison on a variable that may be undef:
Instead of...

if ($possibly_undef eq 'Hello') { ...

[download]

...write:

if ($possibly_undef//'' eq 'Hello') { ...

[download]

Or of course "no warnings 'uninitialized';" if you want to disable it completely, but I don't usually do this.

In reply to Re: Do people find warning for undef with string compare useful? by smls
in thread Do people find warning for undef with string compare useful? by perl-diddler

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