Nice. I always forget about the low-precidence variations. Combining that with GrandFather's reply gives: 
my $x= blahblah...  err return;
... continue using $x

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That reads with the proper "flow" and connotations: if I find an undef after this computation, quit now.

Now what version of Perl introduced err?

later... Apparently not the one I'm using! The construct above gives an error, "missing operator before err?", but the syntax works with or so it's not the precedence, but rather it seems not to know what err means!

The perldoc perlop (I'm reading for Perl 5.10.1 since that's what I'm using) has a section called “Logical or, Defined or, and Exclusive Or”, and it discusses the low-precedence or and xor but doesn't actually mention any kind of "defined or" keyword. How odd.

In reply to Re^2: What's the opposite of // (err) operator? by John M. Dlugosz
in thread What's the opposite of // (err) operator? by John M. Dlugosz

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