in reply to Re: correct usage of class attributes
in thread correct usage of class attributes

It does help, and thanks gjb. I have one more question (at leat), and I hope you don't mind. How do I decleare attribute names, such as: 
$self->{attr_name} = $attr_value

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in your example? Are those done outside the method area with  my or like this: 
...
$self->{height}=6;
$self->{weight}=210;
...

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If so, can you have hashes and arrays? thanks SO much!

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Re: Re: Re: correct usage of class attributes
by gjb (Vicar) on May 05, 2004 at 14:20 UTC

    You don't have to declare them. Simply assigning to $self->{height} will do the trick. After all, the object is just a Perl hash that is blessed, nothing more.

    Of course, you may want to initialize the object attributes to default values so that you know their state. In that case the constructor is a good place to do so (the class method conventionally called new.

    Note that this is just the simplest approach to objects in Perl and definitely not the cleanest of safest, but well, it's good to start with IMHO.

    Hope this helps, -gjb-

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      last question, I promise!!!

      What about if I want something like: $self->{friends} and I want it to be a list or $self->{pets} and I want it to be a hash? like dogs->mike, charlie->cat mary, sal thanks so much!

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        Simple: $self->{friends} = ['John', 'Marie'];, or to add something to that list: push(@{$self->{friends}}, 'Jane');.

        Same story for hashes: $self->{pets}->{dogs} = 'mike'

        You may want to have a look at the tutorials on references and data structures in the perldocs (since the site is down, I can't link you now).

        Hope this helps, -gjb-

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