On 17 Oct 2012, at 15:54, Bill Moseley wrote:

> 
> 
> On Wed, Oct 17, 2012 at 12:34 AM, Tomas Doran <bobtf...@bobtfish.net> wrote:
> 
> 
> This needs a Catalyst release first - I was waiting till there were a few 
> more changes for that, but if it's hurting people now, we could do a new 
> version with just the tiny changes I made to support this.
> 
> By the way, I wonder if it wouldn't be cleaner to use _build_request instead 
> of a builder for the args.   In this case might have to completely override 
> _build_request to inject in the cache -- or make the cache "rw" so that it 
> can be set after _build_request.

No, and the explicit reason it's not cleaner is that 'rw' - would that we could 
change things so that the request object was constructed in it's final 
immutable form!

> Seems like giving the request the app as an attribute would be a bad idea, 
> but not clear what that is. :)
> 

Too much coupling! App has a request has an app - ARGH.

> I've been struggling a bit with hierarchy of classes where I need to pass 
> child construction params down to child constructors.  I've added "parent" 
> attributes to the child classes, manually passed args (as you are doing 
> here), and even had separate config objects that I pass around.  Haven't 
> found anything that I'm that fond of.

You should inject _just_ the dependencies that the class in question needs, 
having explicitly broken them out.

Passing the app down makes the app a 'god object'.

Why would you care? Well, Say you want to persist most session data into the 
DB, but you're happy with progress bars being in memcache - if you pass the 
cache explicitly to the request you can do this trivially, if you pass the 
entire $c or $app down to the request, you cannot do this at all.

Hope this helps!

Cheers
t0m
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