php yield

output.log

Generator
Array
(
    [0] => rewind
    [1] => valid
    [2] => current
    [3] => key
    [4] => next
    [5] => send
    [6] => throw
    [7] => getReturn
    [8] => __wakeup
)

true
0.txt
current '0'



current '1'
0.txt
1.txt



current '2'
0.txt
1.txt
2.txt



current '3'
0.txt
1.txt
2.txt
3.txt



current '4'
0.txt
1.txt
2.txt
3.txt
4.txt



current '5'
0.txt
1.txt
2.txt
3.txt
4.txt
5.txt



current ''
0.txt
1.txt
2.txt
3.txt
4.txt
5.txt
6.txt



current ''
0.txt
1.txt
2.txt
3.txt
4.txt
5.txt
6.txt



current ''
0.txt
1.txt
2.txt
3.txt
4.txt
5.txt
6.txt

TestYield.php

class TestYield
{
    private function clearDir() {
        if (!is_dir('./files')) {
            return;
        }
        if ($handle = opendir('./files')) {
            while (false !== ($entry = readdir($handle))) {
                if ($entry != "." && $entry != "..") {
                    // echo "$entry\n";
                    unlink("./files/{$entry}");
                }
            }
            closedir($handle);
        }
    }
    private function listDir() {
        if (!is_dir('./files')) {
            return;
        }
        if ($handle = opendir('./files')) {
            while (false !== ($entry = readdir($handle))) {
                if ($entry != "." && $entry != "..") {
                    echo "$entry\n";
                }
            }
            closedir($handle);
        }
    }
    private function getGenerator()
    {
        if (!is_dir('./files')) {
            mkdir('./files', 0777);
        }
        $i = 0;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
        yield $i;
        $i++;
        file_put_contents('./files/'.$i.'.txt', "content $i");
    }
    public function run()
    {
        $this->clearDir();
        $generator = $this->getGenerator();
        echo "\n";
        print_r(get_class($generator));
        echo "\n";
        print_r(get_class_methods($generator));
        echo "\n";
        $this->listDir();
        echo $generator->valid() ? "true\n" : "false\n";
        $this->listDir();
        echo "current '{$generator->current()}'\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
        // echo $generator->valid() ? "true\n" : "false\n";
        $generator->next();
        echo "\n\n\n";
        echo "current '{$generator->current()}'\n";
        $this->listDir();
    }
}