CoreSyn: A data type for the Haskell compiler midsection
\begin{code}
+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
module CoreSyn (
Expr(..), Alt, Bind(..), AltCon(..), Arg, Note(..),
CoreExpr, CoreAlt, CoreBind, CoreArg, CoreBndr,
import Type
import Coercion
import Name
-import OccName
import Literal
import DataCon
import BasicTypes
-- Locality
ru_local :: Bool -- The fn at the head of the rule is
-- defined in the same module as the rule
+ -- and is not an implicit Id (like a record sel
+ -- class op, or data con)
+ -- NB: ru_local is *not* used to decide orphan-hood
+ -- c.g. MkIface.coreRuleToIfaceRule
}
| BuiltinRule { -- Built-in rules are used for constant folding
ru_name :: RuleName, -- and suchlike. It has no free variables.
ru_fn :: Name, -- Name of the Id at
-- the head of this rule
- ru_nargs :: Int, -- Number of args that ru_try expects
+ ru_nargs :: Int, -- Number of args that ru_try expects,
+ -- including type args
ru_try :: [CoreExpr] -> Maybe CoreExpr }
+ -- This function does the rewrite. It given too many
+ -- arguments, it simply discards them; the returned CoreExpr
+ -- is just the rewrite of ru_fn applied to the first ru_nargs args
+ -- See Note [Extra args in rule matching] in Rules.lhs
isBuiltinRule (BuiltinRule {}) = True
isBuiltinRule _ = False