Book Image

Haskell High Performance Programming

By : Samuli Thomasson
Book Image

Haskell High Performance Programming

By: Samuli Thomasson

Overview of this book

Haskell, with its power to optimize the code and its high performance, is a natural candidate for high performance programming. It is especially well suited to stacking abstractions high with a relatively low performance cost. This book addresses the challenges of writing efficient code with lazy evaluation and techniques often used to optimize the performance of Haskell programs. We open with an in-depth look at the evaluation of Haskell expressions and discuss optimization and benchmarking. You will learn to use parallelism and we'll explore the concept of streaming. We’ll demonstrate the benefits of running multithreaded and concurrent applications. Next we’ll guide you through various profiling tools that will help you identify performance issues in your program. We’ll end our journey by looking at GPGPU, Cloud and Functional Reactive Programming in Haskell. At the very end there is a catalogue of robust library recommendations with code samples. By the end of the book, you will be able to boost the performance of any app and prepare it to stand up to real-world punishment.
Table of Contents (21 chapters)
Haskell High Performance Programming
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

The HaskellR project


The HaskellR project enables seamless integration between Haskell and the R language. It makes the big repository of R libraries available to Haskell. In essence, HaskellR provides an interpreter that integrates GHCi with R, called H, and a quasi-quoter that enables writing R code into Haskell code.

The first way to use HaskellR is to install H and run it:

$ stack install H
$ stack exec H
>

This basically gives a modified GHCi prompt, where we have full access to both Haskell and R:

> [1..10]
[1,2,3,4,5,6,7,8,9,10]

> let (x,y) = (5, 10) :: (Double, Double)
> H.p [r| y_hs + x_hs + e |]

We access R through the R quasi-quoter. Haskell values simply get a _hs prefix. We can even use Haskell functions from quasi-quoted R expressions, as long as they are lifted to the R monad.