Learning (from) Haskell - An experience report

Functional programming as a programming style and discipline is useful even in languages which are not pure functional languages. By practising programming in a pure functional language like Haskell, programmers can drastically improve the quality of code when coding in other languages as well.

The talk is based on first hand experience of using Haskell in internal courses in our organisation to improve code quality.

This talk will cover Gofer (one of the earliest variants of Haskell) as a teaching tool, including the choice of the language, the features from Haskell that should (and shouldn't) be covered and the obstacles and benefits of the exercise.

 

 
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Outline/structure of the Session

  1. The context - in what environment are the contents of this talk relevant
  2. Why we felt the need for inculcating functional programming habbits in our developers - The desirable characteristics of functional programming style and functional code
  3. Why Haskell? (And why not Scheme).
  4. Introducing Gofer
  5. What aspects of Haskell we focused on (and what we left out)
  6. Applying the learnings to other languages - real world before and after examples
  7. Obstacles and benefits

Learning Outcome

Whether learning functional programming is useful for you or your developers, the effort and investment that would be needed and the benefits you will derive from it.

Target Audience

CTO, Team Leads, Passionate programmers

schedule Submitted 3 years ago

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  • Dhaval Dalal
    By Dhaval Dalal  ~  3 months ago
    reply Reply

    Hi Aditya,

       I am kind of in between - is this talk or more of an experience report that you intend to share?  I think it suits more to be an XR as it would be interesting to see - the journey - did you try this with OO programmers (if at all) ? How Haskell helped in developing better insights to the problems in existing codebase (esp in connection with #5 above) ? and what did you observe during the transition?

    thanks

    • Aditya Godbole
      By Aditya Godbole  ~  2 years ago
      reply Reply

      It is in some sense an XR. But it will also cover technical aspects of what functional programming means outside a pure functional language.

      I will also cover which features from the functional world, if adopted as a discipline, give the most bang for the buck.

      Also, the two sides of the coin, for me, are not OO vs Functional, but Imperative vs Functional. Whether the imperative code was OO is not relevant to this discussion.

      I will also include a few before and after examples in languages like Python, Javascript and Ruby, to illustrate the difference that this exercise made in the typical code produced by programmers.

      • Dhaval Dalal
        By Dhaval Dalal  ~  3 months ago
        reply Reply

        Thanks Aditya for the clarification: Imperative -> Functional.  I was just proding to find where you were coming at this from and hence the question.  It would be nice to see the before -> after transformation after applying the learnings from Haskell.  

        As I understand, the technical aspects and features in the FP land are underpinning this, and I think blending them (not sure if you meant it that way) with the examples from your experience will leave the audience inspired to try it out.  what do you think?

         

        • Aditya Godbole
          By Aditya Godbole  ~  2 years ago
          reply Reply

          Hopefully the before/after examples will give a glimpse of how maintainable code can be written after the discipline picked up by practising functional programming in haskell is applied to other languages. I stress on the word discipline because that is what is required when one is writing in an imperative language. That should serve as the motivation for audience to write code in haskell.

          The bottom line of the talk is this - in haskell you write code in a certain way because there is no choice or because that is the idiomatic way or the path of least resistance. By practising in haskell, you carry forward that discipline to other languages not because you have to, but because you start seeing the value (pun not intended). 

          • Dhaval Dalal
            By Dhaval Dalal  ~  3 months ago
            reply Reply

            Hey Aditya,

               Can you make this as an XR and refactor "Process" section to deliver it from that perspective?

            Thank-you,

            Dhaval.

             

            • Aditya Godbole
              By Aditya Godbole  ~  2 years ago
              reply Reply

              Done. Is there anything else in particular you want to see changed?

              • Naresh Jain
                By Naresh Jain  ~  2 years ago
                reply Reply

                Thanks Aditya. Can you please update your title to Learning (from) Haskell - An Experience Report. This would be more clear to the participants.

  • vimalk
    By vimalk  ~  3 years ago
    reply Reply

    i would not miss this talk!!


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