In OO Perl, it's a good idea to avoid "multiple inheritance" which is when an object belongs to two or more classes. To avoid this problem, Damian Conway offers this bit of code to be placed in the initialization subroutines within a special initialization class (p. 175 of OO Perl) to avoid the problem: 
sub _init
{
   my ($self, %args) = @_;

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   return if $self->{_init}{__PACKAGE__}++; 
   ...   
}

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</code> I think I'm overloaded with too much Perl because I am completely missing how this simple code works. Apparently, the above syntax creates an attribute for the object, causing a return out of the current subroutine if the attribute is non-zero. But how does throwing a class, {__PACKAGE__}, on the right side of an object method call, $self->{_init}, create an attribute?

$PM = "Perl Monk's";
$MCF = "Most Clueless Friar Abbot Bishop";
$nysus = $PM . $MCF;
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In reply to Syntax for preventing repeat object initializations by nysus

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