No subject


Thu Jul 5 12:38:43 CEST 2012


(.), we will build up combinators suitable for working with a wide
array of data structures. These generalize the notions you already
know how to use into a form that is easier to compose, and
simultaneously allow them to be used for monomorphic containers such
as Data.Text. All without compromising on your ability to reason about
them using laws!

Once we've built up some foundations, we'll do a bit of a deep dive,
exploring consequences of this design. We will discuss the efficient
generic programming programming framework exported by lens, and
type-safe Traversal-based zippers.

Familiarity with the Applicative and Traversable classes from the
Haskell base libraries will be helpful (links provided below), but a
basic understanding of the concepts will be introduced we go along.
Attendees should expect to be gobsmacked with a newfound appreciation
for the power of a little (or a lot of) abstraction.

Useful (but not mandatory) references:

The lens library and documentation: http://hackage.haskell.org/package/lens
A previous, more introductory talk on how to use the lenses Edward
Kmett wrote for the scalaz in the Scala programming language:
https://www.youtube.com/watch?v=efv0SQNde5Q
The original Applicative paper:
http://www.soi.city.ac.uk/~ross/papers/Applicative.pdf
Lots of information on Traversable:
http://www.cs.ox.ac.uk/jeremy.gibbons/publications/iterator.pdf
A write-up of this talk, as presented at the Bay Area Haskell Users
Group: http://google-opensource.blogspot.com/2012/10/lenses-folds-and-traversals-haskell.html



More information about the Haskell-Cafe mailing list