optimize with defer logic

[djunny]

No description provided.

[bkrukowski]

What's the goal of this pull request?

[djunny]

less memory useage & higher performance & chain call & better implementation

[bkrukowski]

@djunny

Chain calls

Chain calls look a bit weird to me. I cannot see a big benefit of using

defer($_, $callbackA)->push($callbackB);

instead of

defer($_, $callbackA);
defer($_, $callbackB);

Furthermore, why do we have to register 2 callbacks in consecutive lines? Would not be easier to have just:

defer($_, function() {
    $callbackB();
    $callbackA();
});

?

In my opinion, the above code is more explicit and easier to read. I appreciate your effort, but I have to reject this part.

Design

I really like your way of making the order of callbacks explicit.

            while ($this->count() > 0) {
                \call_user_func($this->pop());
            }

If you are ok with reverting "chain calls" from your pull request, I would like to merge it.

[djunny]

chain calls:

I just return the SplStack object on the basis of the original,

but i dont think it is recommended to use it like that.

so i removed in README

[bkrukowski]

I cannot approve changing the header of this function, I explained it in the previous comment:

Suggested change

	function defer(?SplStack &$context, callable $callback): SplStack
	function defer(?SplStack &$context, callable $callback): void

[bkrukowski]

Please revert those changes