src/Leevel/Di/Container.php
public function exists(string $name): bool
    {
        $name = $this->normalize($name);

        $name = $this->getAlias($name);

        return isset($this->services[$name]) ||
            isset($this->instances[$name]) ||
            $this->existsCoroutine($name);
    }
public function exists(string $name): bool
    {
        $name = $this->normalize($name);

        $name = $this->getAlias($name);

        return isset($this->services[$name]) ||
            isset($this->instances[$name]) ||
            $this->existsCoroutine($name);
    }
服务或者实例是否存在.

@param string $name

@return bool