[Catalyst] Small patch for ConfigLoader

[Brian Cassidy]

Hi Andreas,

> -----Original Message-----
> > I couldnt understand why __HOME__ was only alloved in the beginning
> > of the strings, making it totaly useless for things like dbi driver
> > strings (think dbd:SQLite:__HOME/db/ape.db), so I wrote a small
> > patch to allow such constructs.
>
> its against current cpan for one, and it also kills a warning on
> empty lines (which I like to add for readability)

The latest SVN version already squashes the warnings. So, all that's left is
allowing __HOME__ anywhere in the string. After chatting with mst on IRC a
little bit, we've come up with a possible solution:

Firstly, __HOME__ should not take any params. It will simple be replaced
with the value of $c->path_to( '' );

Secondly, there will be an alternate substitution that takes arguments:
__path_to(db/ape.db)__ -- this will translate to $c->path_to( 'db', 'ape.db'
);

The code could look something like this:

my $v = Data::Visitor::Callback->new(
    plain_value => sub {
        return unless defined $_;
        s[__HOME__][ $c->path_to( '' ) ]e;
        s[__path_to\((.+)\)__][ $c->path_to( split( '/', $1 ) ) ]e;
    }
);

Thoughts?

-Brian