Generator::getReturn

The note by jm at guide42 dot com is inaccurate. Generator::getReturn() does not check the existence of the return statement, but rather whether the function has returned (finished executing).<?phpfunction f(){  yield;}f()->getReturn(); // Exception: Cannot get return value of a generator that hasn't returned$f = f();$f->next(); // NULL$f->getReturn(); // NULL, because having no return statement implies an empty `return;`, and the void return value is resolved to null.

Just to be clear, the value returned by a generator is not yielded while it is running, but is available afterwards through the getReturn() method.One use for this could be to record the output of a generator so that it can be iterated over again without having to reconstruct and re-run the generator. (Indeed, one could write a generator that simply does exactly this for any given iterable.)<?phpfunction generate_squares($n){    $record = [];    for($i = 0; $i <= $n; ++$i)    {        yield ($record[] = $i * $i);    }    return $record;}$squares = generate_squares(10);foreach($squares as $s){    echo $s, ' ';}$recorded = $squares->getReturn();echo "\nThat's [", join(', ', $recorded), "]";?>Recording keys as well would take a bit more work, as generators are free to repeat them but arrays aren't.

I'm not quite sure -- I feel there is an ambiguity issue here with returning a value inside a generator and ->getReturn() method of such generator as I have been able to return an array of sorts, something like this:function dequeue(){try{  foreach($this->buffer->data as $data){ ... }}  return $statistics;}foreach(($generator = $this->dequeue()) as $bdata){.....}if($statistics = $generator->getReturn()){ // generator returns $statistics}Obviously this is not a complete example, but $statistics does become available with the returned array.