[GHC] #15783: Quoting an internal variable causes an error when splicing

19 Oct 2018

      #15783: Quoting an internal variable causes an error when splicing
-------------------------------------+-------------------------------------
           Reporter:  mpickering     |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.6.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 {{{
 {-# LANGUAGE TemplateHaskell #-}
 module A where

 import B

 main = $$f
 }}}

 {{{
 {-# LANGUAGE TemplateHaskell #-}
 module B(f) where

 d = 0

 f = [|| d ||]
 }}}

 Note that `d` is not exported from `B`.

 {{{
 [1 of 2] Compiling B                ( B.hs, B.o )
 [2 of 2] Compiling A                ( A.hs, A.o )

 A.hs:6:8: error:
     • Can't find interface-file declaration for variable B.d
         Probable cause: bug in .hi-boot file, or inconsistent .hi file
         Use -ddump-if-trace to get an idea of which file caused the error
     • In the expression: B.d
       In the result of the splice:
         $f
       To see what the splice expanded to, use -ddump-splices
       In the Template Haskell splice $$f
   |
 6 | main = $$f
 | ^^^
 }}}

 This doesn't seem to happen for untyped quotes/splices.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15783
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