2009/4/30 Olivier Lalonde <olalonde@xxxxxxxxx>:
> Hi all,
>
> Since I can't do $this = new Class(); within my class (it gives an
> error), I was looking for ways to get the same result by other means.
>
> I am actually working on an ORM and trying to implement lazy loading.
>
> $book = $orm->getBook('id'); // returns an Orm object
> $book->load();
>
> // $book should now be a Book instead instead of an Orm instance
>
> Of course, I oversimplified the problem. $book = $orm->getBook('id');
> doesn't return a Book instance right ahead because it is a chained
> method (i.e. $orm->getBook()->where(...)->prefetch(...)->etc....
> Therefore, it _has_ to return an Orm instance.
>
> Now, why not simply add ->load() at the end of the chain? Because it
> adds an extra step for developers that doesn't bring meaningful
> information. Instead of doing $book = $orm->getBook('id');, it would
> mean having to do $book = $orm->getBook('id')->load(); (which is
> longer to type :p). That's why I wanted to implement "lazy loading".
>
> $book = $dorm->getBook('id');
> echo $book->title; // title should be trapped by __set() and it should
> dynamically replace $book by an actual Book instance
>
> I tried doing the following, but PHP doesn't allow it:
>
> class A {
> public function transform() {
> $this = new B();
> }
> }
>
> class B {}
>
> $var = new A();
> $var->transform();
>
> This is not currently supported by PHP and I was wondering if there
> was anyway of getting around the problem, that doesn't involve
> 1) passing $var to the A class i.e:$var->var = $var;
> 2) looping $GLOBALS[]
> 3) using __call,__get and __set to proxy everything to the actual Book object
>
> PS1: don't lecture me about how I'm doing this all wrong. I've looked
> at the problem from every possible angle and this is the only
> solution.
> PS2: Another alternative would be to subclass the Orm object with
> Book, (class Orm extends Book {}), overload all properties/methods so
> we can catch when to load the object... but that would be an extreme
> pain in the ass.
> PS3: Another alternative would be to have a parameter that
> enables/disables chaining.
> $dorm->getBook('id', true); // chain (you now have to add ->load() at
> the end of the chain)
> $dorm->getBook('id', false); // dont chain, this returns a Book instance
>
> The point of all this is to keep the most friendly interface !
>
> Cheers,
> Olivier
>
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>
>
In $orm->getBook('id') should be something similar to ...
$book = new ClassBook('id');
$book->load;
return $book;
surely?
--
-----
Richard Quadling
Zend Certified Engineer : http://zend.com/zce.php?c=ZEND002498&r=213474731
"Standing on the shoulders of some very clever giants!"
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