[Catalyst] Note re config - Documenters and module authors pleasetake note

[Matt Pitts]

Would it be sane to break down the hash merging magic of $c->config into
separate methods? For example, for doing large-scale, pre-setup config
we could have

__PACKAGE__->add_config({ name => 'MyApp', ... });

Which will make use of 'merge_config_hashes' and apply the
C::D::Inhertiable kludging. Then __PACKAGE__->config could just be a
getter of the whole app config which wouldn't need C::D::Inheritable
kludging to prevent the creation a setter in __PACKAGE__.

So, doing things like

__PACKAGE__->config->{foo}{bar} = 'value';

is still safe.

Or, is there some more magic to Class::Data::Inheritable that I'm
missing? 

v/r

-matt 

> -----Original Message-----
> From: Matt S Trout [mailto:dbix-class at trout.me.uk]
> Sent: Thursday, February 07, 2008 7:46 AM
> To: catalyst at lists.scsys.co.uk
> Subject: [Catalyst] Note re config - Documenters and module authors
> pleasetake note
> 
> I keep seeing people doing
> 
> __PACKAGE__->config->{foo}{bar} = 'value';
> 
> This is -not- correct usage, is -not- safe and has undefined results.
> I've
> hacked the implementation of config around quite a bit to minimise
this
> but
> without doing highly expensive (and potentially also dangerous) deep
> clones
> everywhere it can't be made safe.
> 
> The correct thing to do is -
> 
> __PACKAGE__->config(
>   foo => { bar => 'value' }
> );
> 
> Basically, only ever call ->config->{... for getting values.
> 
> If you need to set, call the method as demonstrated above.
> 
> Any documentation or code using the other approach (including some in
> cat
> core) is -wrong- and we need to correct it.
> 
> --
>       Matt S Trout       Need help with your Catalyst or DBIx::Class
> project?
>    Technical Director
> http://www.shadowcat.co.uk/catalyst/
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