Control.Monad.Freer.Trace

Composable handler for Trace effects. Trace allows one to debug the operation of sequences of effects by outputing to the console.

Using http://okmij.org/ftp/Haskell/extensible/Eff1.hs as a starting point.

Documentation

data Trace v

A Trace effect; takes a String and performs output

trace :: Member Trace r => String -> Eff r ()

Printing a string in a trace

runTrace :: Eff '[Trace] w -> IO w

An IO handler for Trace effects