id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
3634	Add traceM, traceShowM and withTrace	MartijnVanSteenbergen		"On haskell-libraries we have [http://thread.gmane.org/gmane.comp.lang.haskell.libraries/12019 discussed] the addition of the following three functions to module Debug.Trace:

{{{
withTrace :: Show a => String -> a -> a
withTrace msg x = trace (msg ++ show x) x

traceM :: Monad m => String -> m ()
traceM msg = trace msg (return ())

traceShowM :: (Show a, Monad m) => a -> m ()
traceShowM = traceM . show
}}}

The current documentation for that module is a little terse so we have also added an example to clarify the use of trace.

The following people have participated in the discussion and all expressed interest, agreement or concerns (but always with constructive comments) in or over the new functions: Philip Hölzenspies, pepe, Lennart Augustsson, Felipe Lessa, Evan !LaForge, Joachim Breitner, Twan van Laarhoven, Ben Franksen, Ian Lynagh, Sean Leather. Please see the thread for more detail.

I have attached a diff that can be applied to the module. Could one of the GHC developers check it and apply it?

Thanks,

Martijn.
"	proposal	closed	normal	Not GHC	libraries/base	6.10.4	wontfix			Unknown/Multiple	Unknown/Multiple	None/Unknown	Unknown