src/Aspose/Storage/Api/StorageApi.php
public function getIsExistAsync(Requests\GetIsExistRequest $request) 
    {
        return $this->getIsExistAsyncWithHttpInfo($request)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }
public function getIsExistAsync(Requests\GetIsExistRequest $request) 
    {
        return $this->getIsExistAsyncWithHttpInfo($request)
            ->then(
                function ($response) {
                    return $response[0];
                }
            );
    }
/*
Operation getIsExistAsync

Check if a specific file or folder exists

@param Requests\GetIsExistRequest $request is a request object for operation

@throws \InvalidArgumentException
@return \GuzzleHttp\Promise\PromiseInterface