reader = $reader; $this->writer = $writer; } /** * Determine if the given environment variable is defined. * * @param string $name * * @return bool */ public function has(string $name) { return $this->reader->read($name)->isDefined(); } /** * Get an environment variable. * * @param string $name * * @return string|null */ public function get(string $name) { return $this->reader->read($name)->getOrElse(null); } /** * Set an environment variable. * * @param string $name * @param string $value * * @return bool */ public function set(string $name, string $value) { return $this->writer->write($name, $value); } /** * Clear an environment variable. * * @param string $name * * @return bool */ public function clear(string $name) { return $this->writer->delete($name); } }