ghc-codo-notation

A notation for comonads, analogous to the do-notation for monads.
Requires the 'TemplateHaskell' and 'QuasiQuotes' extensions.
Example 1:
' {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE QuasiQuotes
import Control.Comonad import Language.Haskell.Codo
foo :: (Comonad c, Num a) => c a -> a foo = [codo| x => extract x + 1 |] '
Example 2:
' import Data.Monoid instance Monoid Double where     mempty =
0.0     mappend = (+)
differentiate f = ((f 0.001) - f 0) / 0.001
minima :: (Double -> Double) -> Bool minima = [codo| f => f' <- differentiate f
&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;
f'' <- differentiate f'
&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;&#x20;
(extract f' &#60; 0.001) && (extract f'' &#62; 0) |] '
Further explanation of the syntax can be found in the following (short) paper:
<http://www.cl.cam.ac.uk/~dao29/drafts/codo-notation-orchard-ifl12.pdf> with a
numer of examples.
Further examples can be found here:
<https://github.com/dorchard/codo-notation>.

          

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License: BSD-3-Clause
URL: https://hackage.haskell.org/package/codo-notation