Beefy Boxes and Bandwidth Generously Provided by pair Networks
Think about Loose Coupling
 
PerlMonks  

Re: Tie::SecureHash and AUTOLOAD'ing

by TheDamian (Priest)
on Apr 10, 2003 at 22:12 UTC ( #249756=note: print w/ replies, xml ) Need Help??


in reply to Tie::SecureHash and AUTOLOAD'ing

AUTOLOAD works fine with Tie::Securehash. Like this...

use Tie::SecureHash; package DogTag; sub new { my ($class, %args) = @_; Tie::SecureHash->new( $class, __name => $args{name}, __rank => $args{rank}, __serial => $args{serial} ); } sub report { my ($self) = @_; print $self->name, "\n"; print $self->rank, "\n"; print $self->serial, "\n"; } sub DESTROY {} # Usually needed when using AUTOLOAD sub AUTOLOAD { my ($self) = @_; $AUTOLOAD =~ s/.*::/__/; return $self->{$AUTOLOAD}; } package main; my $id = DogTag->new(name=>"Smith", rank=>"private", serial=>1234567); $id->report();


Comment on Re: Tie::SecureHash and AUTOLOAD'ing
Download Code
Re: Re: Tie::SecureHash and AUTOLOAD'ing
by forkboy (Sexton) on Apr 11, 2003 at 02:21 UTC
    arh yes, but I can also do this
    package main; my $id = DogTag->new(name=>"Smith",rank=>"private",serial=>'1234567'); print $id->name();
    which somewhat defeats the purpose of Tie::SecureHash. What I really need is an autoloader that correctly enforces the same rules as Tie::SecureHash
      Okay, but first notice that the AUTOLOAD is enforcing encapsulation. You can call attribute accessors, but only ever to retrieve the current values, not to set new ones.

      Remember: encapsulation is not about preventing access to attributes; it's about controlling access to attributes.

      If you want the control that the AUTOLOAD enforces to be identical to the control that Tie::SecureHash enforces (which is a perfectly reasonable thing to want), just code AUTOLOAD accordingly:

      sub AUTOLOAD { my ($self, $newval) = @_; $AUTOLOAD =~ s/.*:://; my $attr; if (exists $self->{$attr=$AUTOLOAD}) { # public attribute always accessible } elsif (exists $self->{$attr="_$AUTOLOAD"}) { croak "Cannot access protected attribute '$attr'" unless caller().isa(ref $self); } elsif (exists $self->{$attr="__$AUTOLOAD"}) { croak "Cannot access private attribute '$attr'" unless caller() eq ref $self; } else { croak "No such attribute ($AUTOLOAD) for object" } $self->{$attr} = $newval if @_ > 1; return $self->{$attr}; }

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://249756]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others contemplating the Monastery: (7)
As of 2014-11-28 16:21 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My preferred Perl binaries come from:














    Results (199 votes), past polls