comment on

The answer to your questions are:

You don't close classes in Perl, so there's no reopening of them.
There are no builtin classes (well, mostly - q.v. the next answer)

All classes in Perl inherit from UNIVERSAL. So, if you want everyone to have a to_yaml method, do this:

{
    no strict 'refs';
    *{ "UNIVERSAL::to_yaml" } = sub {
        # Put some code here.
    };
}
[download]

To redefine a core function, do this:
```
{
    no strict 'refs';
    *{ "CORE::<funcname>" } = sub { ... };
}
[download]
```
Some functions require you to redefine in CORE::GLOBAL:: instead. There's no real rhyme or reason (from the outside looking in) - you can find more by looking at the appropriate documentation.
Perl6 will allow for redefinition of EVERYTHING under the sun, including syntax, yet have those redefinitions be scoped however you want. In other words, the default Perl6 language is just that - the default. TimToady and the rest of the design team has the idea that Perl6 will actually be a group of interrelated languages that can all talk to one another vs. just a single language. And, people will provide modules to extend the language vs. having to edit the source.

My criteria for good software:

Does it work?
Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Reopening builtin classes, redefining builtin functions? by dragonchild
in thread Reopening builtin classes, redefining builtin functions? by Anonymous Monk

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