Re: reference caller object

On Friday 18 September 2009 11:36:08 pm Chris Trahey wrote: > Hey all, thanks for the discussion. > > First, in terms of implimentation, I've gone back and forth between a > few ways to expose it, but it struck me tonight that the most similar > keyword in use currently is $this. Next to that I think would be static. > > But it seems like there is a bigger decision to make than this > feature. Should the language itself impose coding guidlines on > developers? All languages impose guidelines on developers. Grammar does that. :-) > This reference seems notably basic in an OOP language. The Paradigm is > based largely on two concepts: objects and the messages between them. > For each message, the recipient is known (intrinsically) but the > sender is not. It seems like a basic property of a method call that is > not exposed in a semantically appropriate way. "basic in any OOP language" is a useless statement, as "OOP language" is such an ill-defined concept anyway. :-) PHP is a hybrid language. Is Java an OOP language? Is Javascript? Is Python? Is Ruby? They all have extremely different ideas of what "OOP" means, none of which is inherently wrong. From a PHP perspective, as Pawel notes PHP doesn't use full on message passing as its communication mechanism. A function call is not a message pass. Having implicit knowledge about your context (ie, the caller) makes encapsulation, testing, and divide-and-conquer substantially more difficult if not impossible. And really, you're not talking about a caller object but about accessing variables in scope from the next-highest step in the call stack, which may or may not be an object. (Hybrid language, remember. It could be a lambda function as of PHP 5.3, or global scope, or...) If you need a variable from higher in the stack, that's what function parameters are for. -- Larry Garfield larry@garfieldtech.com