When you have an operator paired with an =, that can usually be translated to an easier to understand version. Your examples could be written as: 

$v ||= $w --> $v = $v || $w
$x &&= &y --> $x = $x && $y

$v |= $w  --> $v = $v | $w
$x &= $y  --> $x = $x & $y

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The first set of examples are logical and, and logical or. The or example checks if $v is true, if it is, $v is set to itself, OR it is set to $w. The and example is a little more confusing and I'm not really sure why you would want to use it. If $x is 0, it remains 0, otherwise it is set to $y.

The second set of examples is bitwise and, and bitwise or.

You can look up more information about these operators in perlop

In reply to Re: logical-assignment operators by lostjimmy
in thread logical-assignment operators by apomatix

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