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    1 {-
    2 (c) The University of Glasgow 2006
    3 (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
    4 
    5 \section{Haskell abstract syntax definition}
    6 
    7 This module glues together the pieces of the Haskell abstract syntax,
    8 which is declared in the various \tr{Hs*} modules.  This module,
    9 therefore, is almost nothing but re-exporting.
   10 -}
   11 
   12 {-# LANGUAGE ConstraintKinds #-}
   13 {-# LANGUAGE FlexibleContexts #-}
   14 {-# LANGUAGE FlexibleInstances #-} -- For deriving instance Data
   15 {-# LANGUAGE TypeFamilies #-}
   16 {-# LANGUAGE UndecidableInstances #-} -- Wrinkle in Note [Trees That Grow]
   17                                       -- in module Language.Haskell.Syntax.Extension
   18 -- See Note [Language.Haskell.Syntax.* Hierarchy] for why not GHC.Hs.*
   19 module Language.Haskell.Syntax (
   20         module Language.Haskell.Syntax.Binds,
   21         module Language.Haskell.Syntax.Decls,
   22         module Language.Haskell.Syntax.Expr,
   23         module Language.Haskell.Syntax.Lit,
   24         module Language.Haskell.Syntax.Pat,
   25         module Language.Haskell.Syntax.Type,
   26         module Language.Haskell.Syntax.Extension,
   27 ) where
   28 
   29 import Language.Haskell.Syntax.Decls
   30 import Language.Haskell.Syntax.Binds
   31 import Language.Haskell.Syntax.Expr
   32 import Language.Haskell.Syntax.Lit
   33 import Language.Haskell.Syntax.Extension
   34 import Language.Haskell.Syntax.Pat
   35 import Language.Haskell.Syntax.Type
   36 
   37 {-
   38 Note [Language.Haskell.Syntax.* Hierarchy]
   39 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   40 
   41 Why are these modules not 'GHC.Hs.*', or some other 'GHC.*'? The answer
   42 is that they are to be separated from GHC and put into another package,
   43 in accordance with the final goals of Trees That Grow. (See Note [Trees
   44 That Grow] in 'Language.Haskell.Syntax.Extension'.) In short, the
   45 'Language.Haskell.Syntax.*' tree should be entirely GHC-independent.
   46 GHC-specific stuff related to source-language syntax should be in
   47 'GHC.Hs.*'.
   48 
   49 We cannot move them to the separate package yet, but by giving them
   50 names like so, we hope to remind others that the goal is to factor them
   51 out, and therefore dependencies on the rest of GHC should never be
   52 added, only removed.
   53 
   54 For more details, see
   55 https://gitlab.haskell.org/ghc/ghc/-/wikis/implementing-trees-that-grow
   56 -}
   57 
   58 
   59 -- TODO Add TTG parameter to 'HsModule' and move here.