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Date: Mon, 20 Aug 2012 14:10:46 +0100
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Subject: Re: [PHP-DEV] [RFC] Generators
From: lester@lsces.co.uk (Lester Caine)

Rasmus Lerdorf wrote:
> So how about something like this:
>
> generator function f() {
>    echo "Hello World";
> }
>
> generator function f() {
>    return 1;
> }
>
> generator function f($arg) {
>    if(f!$arg) yield 1;
>    else if($arg<0) return 1;
>    else return;
> }
>
> What does the generator keyword mean in each of these cases? Anything?
> Nothing? Would I see a difference either at compile-time or at execute
> time if I left it out?

Well the same could be said of some of the error messages generated by 'static' 
if E_STRICT is enabled. However an error on the first two saying 'no yield point 
found' would not be unreasonable. In reality a lot of this should simply be 
handled by a good IDE leaving the runtime code as clean as possible?

For the third one ... I'm still waiting for some clarification on how yield is 
SUPPOSED to work anyway? If you are using a 'generator' to return a sequence of 
data elements, then just what does happen between each call to the generator ... 
DOES the generator get called for each value until something flags there are no 
more? I still don't see the advantage of restructuring how things are called to 
get around a problem which can just as easily be solved by proper design in the 
first place.

-- 
Lester Caine - G8HFL
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