Re: [PHP-DEV] Using child classes/interfaces as desired type hints

2010-10-07 Thread Ferenc Kovacs 
On Thu, Oct 7, 2010 at 7:56 AM, Nathan Nobbe quickshif...@gmail.com wrote:

 Hi,

 Probly rehashing an old conversation here, but I'm wondering why the
 following isn't supported

 ?php
 abstract class AbstractServer {}
 class ConcreteServer extends AbstractServer {}

 abstract class AbstractClient {
  abstract function doStuff(AbstractServer $o);
 }

 class ConcreteClient extends AbstractClient {
  function doStuff(ConcreteServer $o) {}
 }
 ?

 This results in a fatal
 Fatal error: Declaration of ConcreteClient::doStuff() must be compatible
 with that of AbstractClient::doStuff() in
 /Users/quickshiftin/gitRepos/timberline/php-api-v15-client/testOverride.php
 on line 11

 I was reading a few posts from way back when

 http://marc.info/?t=10777490481r=1w=2

 yet still find myself wondering.  I think it can be said here that if
 there's a contract defined by AbstractClient::doStuff, that same contract
 is
 honored by ConcreteClient::doStuff.  I also think changing the language to
 support this notion wouldn't raise BC issues for the most part (at all?)
 since at the moment you're forced to move to the lowest common denominator
 in the tree, in this case

 class ConcreteClient extends AbstractClient {
  function doStuff(AbstractServer $o) {}
 }

 your feedback appreciated,

 -nathan



It was discussed recently:

http://marc.info/?l=php-internalsm=128220433328115w=2

Tyrael

Re: [PHP-DEV] Using child classes/interfaces as desired type hints

2010-10-07 Thread Ionut G. Stan 

On 07/Oct/10 8:56 AM, Nathan Nobbe wrote:

Hi,

Probly rehashing an old conversation here, but I'm wondering why the
following isn't supported

?php
abstract class AbstractServer {}
class ConcreteServer extends AbstractServer {}

abstract class AbstractClient {
   abstract function doStuff(AbstractServer $o);
}

class ConcreteClient extends AbstractClient {
   function doStuff(ConcreteServer $o) {}
}
?


Here's the problem:

class ConcreteServer2 extends AbstractServer
{}

Now, ConcreteClient can't receive an instance of ConcreteServer2 as an 
argument, although the initial hint, AbstractServer would have allowed it.


--
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Re: [PHP-DEV] Using child classes/interfaces as desired type hints

2010-10-07 Thread Richard Lynch 
On Thu, October 7, 2010 12:56 am, Nathan Nobbe wrote:
 ?php
 abstract class AbstractServer {}
 class ConcreteServer extends AbstractServer {}

 abstract class AbstractClient {
   abstract function doStuff(AbstractServer $o);
 }

 class ConcreteClient extends AbstractClient {
   function doStuff(ConcreteServer $o) {}
 }
 ?

 This results in a fatal
 Fatal error: Declaration of ConcreteClient::doStuff() must be
 compatible
 with that of AbstractClient::doStuff() in
 /Users/quickshiftin/gitRepos/timberline/php-api-v15-client/testOverride.php
 on line 11

 I was reading a few posts from way back when

 http://marc.info/?t=10777490481r=1w=2

 yet still find myself wondering.  I think it can be said here that if
 there's a contract defined by AbstractClient::doStuff, that same
 contract is
 honored by ConcreteClient::doStuff.  I also think changing the
 language to
 support this notion wouldn't raise BC issues for the most part (at
 all?)
 since at the moment you're forced to move to the lowest common
 denominator
 in the tree, in this case

 class ConcreteClient extends AbstractClient {
   function doStuff(AbstractServer $o) {}
 }

 your feedback appreciated,

I can see why you think it should work, but have you considered all
the possible combinations of children/parent abstract/concrete
classes, and what happens when you do:

class QuickMixClient extends ConcreteClient {
  function doStuff(AbstractServer $o) {}
}

class QuickMixServer extends AbstractServer {
}

$quickie = new QuickMixServer;
$client = new QuickMixCilent;
$client-doStuff($quickie);

Kosher?  Or not?

It's kosher for the QuickMix doStuff, but does not satisfy the
ConcreteServer requirement of ConcreteClient.

So does PHP need to examine every method on every class, and then
complain at compile time?...

That sounds painful to me...
.
.
.



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[PHP-DEV] Using child classes/interfaces as desired type hints

2010-10-06 Thread Nathan Nobbe 
Hi,

Probly rehashing an old conversation here, but I'm wondering why the
following isn't supported

?php
abstract class AbstractServer {}
class ConcreteServer extends AbstractServer {}

abstract class AbstractClient {
  abstract function doStuff(AbstractServer $o);
}

class ConcreteClient extends AbstractClient {
  function doStuff(ConcreteServer $o) {}
}
?

This results in a fatal
Fatal error: Declaration of ConcreteClient::doStuff() must be compatible
with that of AbstractClient::doStuff() in
/Users/quickshiftin/gitRepos/timberline/php-api-v15-client/testOverride.php
on line 11

I was reading a few posts from way back when

http://marc.info/?t=10777490481r=1w=2

yet still find myself wondering.  I think it can be said here that if
there's a contract defined by AbstractClient::doStuff, that same contract is
honored by ConcreteClient::doStuff.  I also think changing the language to
support this notion wouldn't raise BC issues for the most part (at all?)
since at the moment you're forced to move to the lowest common denominator
in the tree, in this case

class ConcreteClient extends AbstractClient {
  function doStuff(AbstractServer $o) {}
}

your feedback appreciated,

-nathan