# waitgroup
示例代码：
~~~php
go(function (){
$ret = [];
$wait = new \EasySwoole\Component\WaitGroup();
$wait->add();
go(function ()use($wait,&$ret){
\co::sleep(0.1);
$ret[] = time();
$wait->done();
});
$wait->add();
go(function ()use($wait,&$ret){
\co::sleep(2);
$ret[] = time();
$wait->done();
});
$wait->wait();
var_dump($ret);
});
~~~
