In this workshop we explore several areas of advances that make up Modern Haskell.

(This is an experiential workshop, we will code together, and explore ideas together from first principles. You will need GHC 7.10 and up.)

Patterns for IO

Experience the 3 styles of IO programming in Haskell, in the order in which they evolved:

* imperative style (the status quo)
* Lazy IO and its limitations
* Iteratee IO, the solution to Lazy IO

As we compare the different styles, we will pay attention to

* what controls evaluation
* space and resource management
* the relationship between producer and consumer

From Foldable, Traversable to Lenses

We follow the evolution of fold and map on lists, to their generalisation over arbitrary types with the Foldable and Traversable type-classes. 

The Lens library raises Foldable and Traversable to an even higher level of abstraction. We will see how the Lens library gives a unified vocabulary for traversal of arbitrary data structures.

Functor, Applicative, Arrow, Monad

These data types fall on a spectrum of power and generality (Functor being the most general, and Monad the most powerful). By experiencing how these types differ in the way they compose, we can gain a clearer understanding of where and how each type may be used.

Datatype Generic Programming (bonus material)

This style of Haskell programming is based on a simple technique: instead of defining functions for ad-hoc types, we deconstruct our types into a more fundamental type representation, and then write generic functions against the lower-level type. These generic functions are impervious to changes in the original, higher-level data types.

We will experience datatype generic programming from first principles, and along the way uncover the key ingredient in the magic sauce called GHC.Generics.

 
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Outline/structure of the Session

  • Introductions
  • Modern Haskell overview
  • Patterns for IO
  • From Foldable, Traversable to Lenses
  • Functor, Applicative, Arrow, Monad
  • Datatype Generic Programming (bonus material)
  • Group discussion 

Learning Outcome

  • Gain an overview and experience some key parts of Modern Haskell.
  • This is an experiential workshop. Participants will be invited to code along with the instructor.

Target Audience

If you have a grasp of Haskell 98 and are ready to advance to modern idiomatic programming, this workshop is for you.

Prerequisite

  • Basic knowledge of functional programming in Haskell 98.
  • Bring your machine, or bring a friend with a machine! Pre-install GHC 7.10 and up. 
schedule Submitted 1 month ago

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  • Dhaval Dalal
    By Dhaval Dalal  ~  1 month ago
    reply Reply

    Looks good to me!


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