Discussion Forum

Haskell binding for GRAKN Version 1.4.2


I found the repository graknLabs/grakn-haskell on GitHub.
However, I am having two problems with it:

  • stack install grakn throws a build error (see code below)
  • the library seems to be for version 1.0.0 but the current GRAKN version is version 1.4.2

Is there any version of this library for the current GRAKN version? And if not: Is this repository useable with the current GRAKN version?
Is this build error known? And if so, how do I resolve it?

Thanks very much for your help :slight_smile:

the error occurring when building grakn-haskell

        /tmp/stack9176/grakn-0.3.0/src/Grakn/Client.hs:83:53: error:
        • Couldn't match expected type ‘ClientEnv’
                      with actual type ‘Maybe
                                        -> ClientEnv’
        • Probable cause: ‘env’ is applied to too few arguments
          In the second argument of ‘runClientM’, namely ‘env’
          In a stmt of a 'do' block:
            runClientM (graqlGet opts (queryString query) ks) env
          In the expression:
            do manager <- newManager defaultManagerSettings
               let env = ClientEnv manager u
               runClientM (graqlGet opts (queryString query) ks) env
    83 |   runClientM (graqlGet opts (queryString query) ks) env

Hi @w.fabian.schneider,

We’re very sorry that grakn-haskell is now completely out of date with the current Grakn version. Grakn server has a new communication protocol, via gRPC, and we will need to reimplement grakn-haskell with the new protocol. We’d be more than happy to help you guide you with the development if you want to take a stab at implementing the client-driver in Haskell. Give us a shout if you think you’d like to! Otherwise, we may pick it up sometime next year.

Interested in implementing a new Haskell client. I love the expressiveness and simplicity of the old one and it’s a shame it has become outdated.

Here’s a documentation to help you implement a new Grakn Client, e.g. in Haskell, @creatorrr : https://dev.grakn.ai/docs/client-api/new-client

Feel free to reach out if you need any help! We’d love to see a Grakn Haskell client too!