in reply to Bless to use my'd $var outside of block?

The typical use of bless is to identify a variable as an object belonging to a certain package / class. Of course, you want to be able to use objects outside the scope in which they're declared, but it's not bless that works this trick, it's simply the fact that the blessed reference is returned by your typical constructor: 

sub new {
    my ($class, @args) = @_;
    my $self = {};
    # do something with @args, use it to populate hashref
    bless $self, $class;
    $self;  #returns $self (reference to a hash)
}

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This is what a constructor does, creates a new instance and returns it.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

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(tye)Re: Bless to use my'd $var outside of block?
by tye (Sage) on Feb 14, 2001 at 21:20 UTC

    I'd disagree that you are talking about "scope". $self goes out of scope at the end of the subroutine but because Perl uses reference counting, the object that $self references is not destroyed until all references to it go away.

    Since you return a reference to that object, the caller will (probably) have a reference to the object until their variable goes out of scope or they overwrite the value of that variable.

    Perl's reference counting means that you don't have to worry about things getting free()d before you are done with them (unlike C). You might have to worry a bit about things not getting free()d even though you are done with them, but I won't go into that here.

            - tye (but my friends call me "Tye")
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