@hackage monadloc0.1

This package defines a class for monads which can keep a monadic call trace.

. See http://pepeiborra.posterous.com/monadic-stack-traces-that-make-a-lot-of-sense for more information.

A preprocessor is provided which can insert calls to withLoc before every monadic statement in a module.

To invoke the preprocessor, add the following pragma at the top of a source file:

{-# OPTIONS_GHC -F -pgmF MonadLoc #-}

together with an import for the Control.Monad.Loc module

This package provides no implementation of the MonadLoc interface. Currently the only package that does so is "control-monad-exception", but any other package can implement it and provide monadic call traces.