Re: single instance shared with module

[jynx]

in reply to single instance shared with module

Brothers smack me down if i'm wrong, but recently i used something similar to this code to do what you're describing:

#!/usr/bin/perl -w
use strict;

package foo;

{
  my $self = {
    foo => bar
  };

  sub new {
    return bless $self, shift;
  }

  sub get_obj {
    return UNIVERSAL::isa($self, 'foo')
    # or not as cool:
    #return ref($self) eq 'foo'
      ? $self
      : goto &new;
  }
}

This not only makes new instances when you want them, it also can pass on old instances to any class that requires it and uses the 'get_obj' method.

Whether this is Good Coding(tm) or not, i can't say, but it's worked for me (and i might change what i have, depending on how monks respond to this :)

jynx

Update: Added the UNIVERSAL::isa call and commented out the ref($self) call due to podmaster's suggestion. Could someone please elaborate on why UNIVERSAL::isa is better?

Update2: Whoops. Put the args for UNIVERSAL::isa in wrong order. Hmm, i tested it before i posted and it seemed to work fine the other way as well. Tested again and apparently i was smoking crack. Mental note: RTFM first next time! ;-)

[Solo]

In brief, UNIVERSAL::isa allows for inheritance, while ref($self) doesn't.