"Programming Perl 3rd" states it a little differently:

Regardless of which kind of assignment operator you use, the final value of the variable on the left is returned as the value of the assignment as a whole.

So you can look at it like this:

my $result = 'hello';
$result or die "I'm dead";

$result = undef; 
$result or die "I'm dead down here.";

--output:--
I'm dead down here. at line 5.

[download]

The fact that a value is returned by the assignment operator let's you do this:

my ($x, $y, $z);
$x = $y = $z = 20;
print "$x $y $z";

--output:--
20 20 20

[download]

The rightmost assignment executes first.

In reply to Re: understanding this database error code handling by 7stud
in thread understanding this database error code handling by Anonymous Monk

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