Beefy Boxes and Bandwidth Generously Provided by pair Networks
Just another Perl shrine
 
PerlMonks  

Re^7: Teach him a lesson with facts

by adrianh (Chancellor)
on Feb 23, 2003 at 18:34 UTC ( #237922=note: print w/replies, xml ) Need Help??


in reply to Re: Re: Re: Re: Re: Re: Teach him a lesson with facts
in thread Teach him a lesson with facts

As with the rest of Perl's object system, inheritance of one class by another requires no special syntax to be added to the language.

Inheritance didn't need extra syntax (it's just assigning to @ISA). Method invocation did.

The -> operator denotes a referance, which has plenty of use outside OO. In this case, were referancing a subroutine from a bless'd variable. I'm not sure about SUPER::.

Well, since references and OO came along in the same release you could argue that the syntax needed to be added for OO ;-)

While the lexical item "->" is the same, the syntax for $object->method is different from $arrayref->[...], $hashref->{...}, etc. It needed to be added for OO (just as we got $coderef->(...) syntax added in 5.003_98 - as the result of a bet I seem to recall)

While something like indirect object syntax was around in perl4 (witness print FILEHANDLE) I think it disingenuous to call it the same syntax as method $object and method Package - hacking of the parser was necessary.

Replies are listed 'Best First'.
Re: Re: Re: Re: Re: Re: Re: Re: Teach him a lesson with facts
by Anonymous Monk on Feb 23, 2003 at 18:48 UTC
    ;-) Pure tech discussion.

    One problem with Perl OO is that it does not deliver everything OO requires in theory. That we all see it, and I saw you agreed.

    Another big problem I see with Perl OO is that, becasue of Perl OO is usually implemented as hash, and Perl hash takes lots of memory, this "bad" combination actually make things worse.

    I think something need to be done about this, before Perl's OO can be 100% accepted by me, actually not just me ...
      One problem with Perl OO is that it does not deliver everything OO requires in theory. That we all see it, and I saw you agreed.

      Actually, what I said was "It lacks useful things like direct support for private methods/attributes. However, these can be implemented using other language features. It's rarely an issue in real world code in my experience." (my emphasis).

      Perl's OO model has good and bad points. Personally I prefer Perl's OO and dynamic typing to Java's lack of multiple-implementation inheritance and lack of generic classes.

      I'm not anti-strong typing. When done well (e.g. Eiffel) it can be a god send. With Java's lack of generics it can be a complete pain.

      Another big problem I see with Perl OO is that, becasue of Perl OO is usually implemented as hash, and Perl hash takes lots of memory, this "bad" combination actually make things worse.

      If memory is an issue. Like speed it often isn't. When it is, there are alternate mechanisms for representing objects. I have never had memory problems due to using hashes as objects.

      I think something need to be done about this, before Perl's OO can be 100% accepted by me, actually not just me ...

      Perl 6 will be providing most of what is "hard" to do directly in Perl 5.

      If you're unhappy with Perl 5's "default" OO model you have the flexibility to write your own. Witness such neat modules as Class::Contract.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://237922]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others romping around the Monastery: (10)
As of 2018-09-24 13:07 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    Eventually, "covfefe" will come to mean:













    Results (191 votes). Check out past polls.

    Notices?
    • (Sep 10, 2018 at 22:53 UTC) Welcome new users!