freer-simple-1.2.1.2: A friendly effect system for Haskell.
Copyright(c) 2016 Allele Dev; 2017 Ixperta Solutions s.r.o.; 2017 Alexis King
LicenseBSD3
MaintainerAlexis King <lexi.lambda@gmail.com>
Stabilityexperimental
PortabilityGHC specific language extensions.
Safe HaskellSafe-Inferred
LanguageHaskell2010

Control.Monad.Freer.Trace

Description

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.

Synopsis

Documentation

data Trace a where Source #

A Trace effect; takes a String and performs output.

Constructors

Trace :: String -> Trace () 

trace :: Member Trace effs => String -> Eff effs () Source #

Printing a string in a trace.

runTrace :: Eff '[Trace] a -> IO a Source #

An IO handler for Trace effects.