Source Location of DataCon objects in GHC 7.4.1 API

Simon Marlow marlowsd at
Mon Jun 4 11:56:06 CEST 2012

On 01/06/2012 10:24, JP Moresmau wrote:
> Hello
> I have a failing test in BuildWrapper when moving from GHC 7.0.4 to
> 7.4.1. As far I can tell, in the TypecheckedSource I get DataCon
> objects that have no location info, and hence I can't retrieve them by
> location... Which is useful in a IDE (tell me what's under my mouse
> cursor, tell me where else it's used).
> Given the simple data declaration:
> data DataT=MkData {name :: String}
> In 7.0.4 I obtain a hierarchy that ends in FunBind (on a Var called
> "name")/MatchGroup/Match/ConPatOut and the contained DataCon named
> "MkData" has a SrcSpan associated with it, and so do the Var,
> MatchGroup and Match.
> In 7.4.1 I have the same hierarchy but the DataCon tells me "no
> location info". The Var "name" has a location, but the MatchGroup and
> Match don't either.
> Is it a normal change? Do I need to change something in the way I load
> the module? Is it a regression?

It sounds like a regression.  Please create a ticket and we'll look into it.


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