Safe Haskell	None
Language	Haskell98

Debug.Trace.Compat

Synopsis

Documentation

traceId :: String -> String

Like trace but returns the message instead of a third value.

Since: 4.7.0.0

traceShowId :: Show a => a -> a

Like traceShow but returns the shown value instead of a third value.

Since: 4.7.0.0

traceM :: Monad m => String -> m ()

Like trace but returning unit in an arbitrary monad. Allows for convenient use in do-notation. Note that the application of trace is not an action in the monad, as traceIO is in the IO monad.

... = do
  x <- ...
  traceM $ "x: " ++ show x
  y <- ...
  traceM $ "y: " ++ show y

Since: 4.7.0.0

traceShowM :: (Show a, Monad m) => a -> m ()

Like traceM, but uses show on the argument to convert it to a String.

... = do
  x <- ...
  traceMShow $ x
  y <- ...
  traceMShow $ x + y

Since: 4.7.0.0