Annotation restriction is not respected while generating Annotation via TH

[Edward Z. Yang]

Hello magesh,

Sounds like a bug.  Could you file a ticket in the GHC Trac,
and CC alanz who had been most closely associated with annotations.

Thanks,
Edward

Excerpts from magesh b's message of 2015-05-05 01:21:33 -0700:
> As per user guide one of the restriction in annotating value is
>     . The binder being annotated must be declared in the current module
> 
> But when I use TH to generate the annotation above restriction is not
> respected.
> Below is the minimal test case to reproduce the issue
> 
> ---- Ann.hs
> 
> {-# LANGUAGE TemplateHaskell #-}
> module Ann where
> 
> import Language.Haskell.TH
> 
> -- {-# Ann id "Orphan Ann for id" #-}  -- *Rightly produces error "Not in
> scope: ‘id’"*
> 
> $(pragAnnD (ValueAnnotation 'id) [|"Orphan Ann for id"|] >>= return .
> return) --* Ideally this should have produced same error as above*
> ---- End of Ann.hs
> 
> ---- Main.hs
> 
> {-# LANGUAGE TemplateHaskell #-}
> module Main where
> 
> import Ann ()
> import Language.Haskell.TH
> 
> ann :: [String]
> ann = $((reifyAnnotations (AnnLookupName 'id) :: Q [String]) >>= (\anns ->
> [|anns|]))
> --err = 'a' && True  -- Uncomment to introduce compile error
> main :: IO ()
> main = print ann
> 
> ---- End of Main.hs
> 
> Also there is another bug in reifying the Orphan Annotations.
> In the above example Main.hs depends on Ann.hs which defines Annotation for
> `id`
> When Main.hs compiles fine in the first go, its is able to retrieve the
> annotation for `id`
> Instead, if Ann.hs compiled successfully and Main.hs failed to compile and
> when you later fix the Main.hs error, it is not able to retrieve that
> annotation without recompiling Ann.hs
> 
> Regards,
> Magesh B