What is the Haskell Criterion library used for?

What is the Haskell Criterion library used for?

The Haskell Criterion library is used for performance measurement and benchmarking in Haskell programs.

How do I install the Criterion library?

You can install the Criterion library using Cabal with the command: cabal install criterion.

Can you give me an example of how to use it?

Sure! Here's a simple example:

import Criterion.Main

main :: IO ()
main = defaultMain [
    bgroup "example" [
        bench "fib 20" $ whnf fib 20,
        bench "fib 30" $ whnf fib 30
    ]
]

fib :: Integer -> Integer
fib 0 = 0
fib 1 = 1
fib n = fib (n - 1) + fib (n - 2)

What are some common use cases for benchmarking?

Common use cases include comparing algorithm performance, optimizing code, and ensuring that changes do not degrade performance.