So why is the first idiom "suboptimal"?

I haven't looked up that passage in the Camel Book, so I'm not sure what it's referring to... but maybe it's trying to point out that 'if ($_=<FH>) ...' could evaluate to false in circumstances where you don't want it to be false (the line being empty or zero). Just a guess though.

(Update: crossed out "empty", because - upon rethinking - I can't really come up with any case where $_ would be the emtpy string — not even when fiddling with the input record separator...)

Update 2: ikegami actually did find a variant where <> can return an empty string...  So, I might in theory un-strike that part again. But I won't — I guess it's unlikely anyone will run into this case by accident :)

In reply to Re: Doubt on defined-ness by almut
in thread Doubt on defined-ness by waldner

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