reference caller object View as Markdown

If the object needs to behave differently based on who called it, there's
already a very easy way to do that:

class A {
function foo() {
$b = new B();
$b->bar($this);
}
}

class B {
function bar($caller) {
if ($caller instance of A) {
// ...
}
}
}

That's also therefore much more self-documenting and easier to test (because
you can simulate what gets passed in) than a magic keyword. I don't see a
need for new magic constants here.

On Wednesday 16 September 2009 3:59:16 pm Chris Trahey wrote:

(Please direct me elsewhere if necessary, this is a feature request)

It would be handy to allow a method to behave differently based on who is
calling it.
the function I am looking for would essentially do this:

function getCaller(){
$bt = debug_backtrace();
return $bt[2]['object'];
}
But of course, there is a lot of uneccessary processing with that call.
Perhaps it could be implimented similar to "self" and "parent" (actualy
more like "static") keywords.

So you could do:
public function registerMe() {
if( ! (caller instanceof 'my_interface')) throw new dev_execption();
if( ! ($this->authenticateMod(caller))) throw new admin_exception('module
not active');
$this->loadedMods[caller->module_id()] = caller;
return caller->onLoad();
}

Chris Trahey
Web Applications Developer
Database Administrator
CSISD [Technology]

--
Larry Garfield
larry@garfieldtech.com

(Please direct me elsewhere if necessary, this is a feature request)

It would be handy to allow a method to behave differently based on who is
calling it.
the function I am looking for would essentially do this:
.. snip ..

Type hinting would be a clean approach, I can not see a argument why
the below would be less correct.

public function registerMe(Loadable $oLoadable) {
if( ! ($this->authenticateMod($oLoadable))) throw new
admin_exception('module
not active');
$this->loadedMods[$oLoadable->module_id()] = $oLoadable;
return $oLoadable->onLoad();
}

2009/9/17 Chris Trahey ctrahey@csisd.org:

It seems worthwhile in a service-provider situation where you do not wish to
enforce use of $this in service consumers.
The service provider can impliment caller without modifying existing code.

Semantically, it should be considered redundant to pass $this in a method
call. There should be an implicit way for a message recipient to determine
who is sending the message, in a uniform way (not left up to the consumers
of your API to impliment).

Thanks for your consideration.

Chris Trahey
Sent from my iPhone

If the object needs to behave differently based on who called it, there's
already a very easy way to do that:

class A {
 function foo() {
  $b = new B();
  $b->bar($this);
 }
}

class B {
 function bar($caller) {
  if ($caller instance of A) {
     // ..
  }
 }
}

That's also therefore much more self-documenting and easier to test
(because
you can simulate what gets passed in) than a magic keyword.  I don't see a
need for new magic constants here.

On Wednesday 16 September 2009 3:59:16 pm Chris Trahey wrote:

(Please direct me elsewhere if necessary, this is a feature request)

It would be handy to allow a method to behave differently based on who
is
calling it.
the function I am looking for would essentially do this:

function getCaller(){
      $bt = debug_backtrace();
      return $bt[2]['object'];
}
But of course, there is a lot of uneccessary processing with that call.
Perhaps it could be implimented similar to "self" and "parent" (actualy
more like "static") keywords.

So you could do:
public function registerMe() {
      if( ! (caller instanceof 'my_interface')) throw new
dev_execption();
      if( ! ($this->authenticateMod(caller))) throw new
admin_exception('module
not active');
      $this->loadedMods[caller->module_id()] = caller;
      return caller->onLoad();
}

Chris Trahey
Web Applications Developer
Database Administrator
CSISD [Technology]

--
Larry Garfield
larry@garfieldtech.com

--

Isn't this exactly what the backtrace is for?

--

Richard Quadling
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