Composable Contravariant Comonadic Logging Library.

Implementation of the co-log logging based on the polysemy extensible effects library.

The ideas behind this package are described in the following blog post:

• co-log: Composable Contravariant Combinatorial Comonadic Configurable Convenient Logging

For the taggless final implementation of the co-log ideas se the following package:

• co-log

co-log-polysemy

co-log-polysemy package is a implementation of the co-log-core logging based on the polysemy extensible effects library.

How to use

co-log-polysemy is compatible with the following GHC versions - supported versions

In order to start using co-log-polysemy in your project, you will need to set it up with these easy steps:

1. Add the dependency on co-log-polysemy in your project's .cabal file. For this, you should modify the build-depends section according to the below section:

   build-depends: base ^>= LATEST_SUPPORTED_BASE
                , co-log-core ^>= LATEST_VERSION
                , polysemy ^>= LATEST_VERSION
   

2. To use this package, refer to the below example

   module Main (main) where
   
   import Prelude hiding (log)
   
   import Polysemy (Member, Sem, runM)
   
   import Colog.Core.IO (logStringStdout)
   import Colog.Polysemy (Log, log, runLogAction)
   
   
   example :: Member (Log String) r => Sem r ()
   example = do
        log @String "First message..."
        log @String "Second message..."
   
   main :: IO ()
   main = runM $ runLogAction @IO logStringStdout example