in reply to Re^5: Variable assignment error checking
in thread Variable assignment error checking

It is not! In this expression: 

$var = func($var) || $var;

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the return value of func($var) will be assigned to $var if func($var) is true, otherwise the value of $var. In this expression 

$var ||= func( $var );

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the return value of func($var) will be assigned to $var if $var is false.

Completely different logic!

The expression $var ||= func( $var ); is shorthand for $var = $var || func( $var );. Can you spot the difference?

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Re^7: Variable assignment error checking
by Anonymous Monk on Dec 15, 2013 at 10:36 UTC 
    $var = $var || func( $var );
$var = func( $var ) || $var;

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    They're certainly logically equivalent if we disregard the short-circuiting nature of operators. (Though the mathematics branch of logic generally deals with no other return values than true and false...)
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[d/l]

      As you say, only if we only worry about true or false... 

      my $var = 5;
sub func { 10 };

print $var || func($var), "\n";
print func($var) || $var, "\n";

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[reply]
[d/l]

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