"why should you have to for something that could not possibly by "by accident""

Explain. How could your use of undef in your example, be "by accident"? 

$s = substr($s,0,1) . undef . substr($s,3);

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The rest. Equally misjudged.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re^6: Use of uninitialized value in substr by BrowserUk
in thread Use of uninitialized value in substr by BrowserUk

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