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Re: singleton in php?




On 02.09.2018 at 22:15, Jeffry Killen wrote:

> I have been trying to get a better understanding of "singleton".
> 
> It is defined as a class that can only produce one instance of 
> itself.
> 
> In the online explanation, that is accomplished by a 
> private constructor function that produces an instance
> of the class within its instance.
> 
> But in php I am of the understanding that a constructor
> function has to be made public and can't return anything.
> 
> Here is the online reference I am looking at:
> https://www.techopedia.com/definition/15830/singleton
> 
> So, at some point it seems that the class instance has to
> be exported via a return statement at some point, otherwise
> how would it be used in other code?
> 
> Is there a part of the manual that addresses this?

There has been a manual page about OOP design patterns[1], but it has
been removed from the PHP manual (IMO, rightly so, since this is out of
scope).  Nonetheless, the part about singletons might still be worth
reading.

[1]
<http://svn.php.net/viewvc/phpdoc/en/trunk/language/oop5/patterns.xml?revision=313136&view=markup&pathrev=331456>

-- 
Christoph M. Becker