BetterReflection\Reflection\ReflectionFunctionAbstract::setBodyFromString PHP Method

    public function setBodyFromString($newBody)
    {
        if (!is_string($newBody)) {
            throw new \InvalidArgumentException('Body parameter must be a string');
        }
        $this->node->stmts = (new ParserFactory())->create(ParserFactory::PREFER_PHP7)->parse('<?php ' . $newBody);
    }