That's exactly what happens to the 4th arg of substr.

No it's not!. It replaces (a potentially null), part of the target string. That is not concatenation. Maybe a limitaion of your english?

Of course you can pass an undefined value to substr by accident..

Did I say you couldn't? What don't you understand about "explicit undef"?

ah! There wasn't even an allusion to this..

You think? Read again.

It's not one of those cases where I can't provide concrete explanation or example. It just reeks of trouble..

Ha! Do it! But you won't be getting counter-argument from me. Been down that road to many times and it is pointless.

You always arrive at a conclusion and then set out to prove it, rather than examine the up & downsides and then reach a conclusion.

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^4: Use of uninitialized value in substr by BrowserUk
in thread Use of uninitialized value in substr by BrowserUk

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