--- /dev/null
+
+% (c) The AQUA Project, Glasgow University, 1994-1998
+%
+\section[FiniteMap]{An implementation of finite maps}
+
+``Finite maps'' are the heart of the compiler's
+lookup-tables/environments and its implementation of sets. Important
+stuff!
+
+This code is derived from that in the paper:
+\begin{display}
+ S Adams
+ "Efficient sets: a balancing act"
+ Journal of functional programming 3(4) Oct 1993, pp553-562
+\end{display}
+
+The code is SPECIALIZEd to various highly-desirable types (e.g., Id)
+near the end.
+
+\begin{code}
+
+module FiniteMap (
+ FiniteMap, -- abstract type
+
+ emptyFM, unitFM, listToFM,
+
+ addToFM,
+ addToFM_C,
+ addListToFM,
+ addListToFM_C,
+ delFromFM,
+ delListFromFM,
+
+ plusFM,
+ plusFM_C,
+ minusFM,
+ foldFM,
+
+ intersectFM,
+ intersectFM_C,
+ mapFM, filterFM,
+
+ sizeFM, isEmptyFM, elemFM, lookupFM, lookupWithDefaultFM,
+
+ fmToList, keysFM, eltsFM
+
+ , bagToFM
+
+ ) where
+
+#include "HsVersions.h"
+#define IF_NOT_GHC(a) {--}
+
+#if defined(DEBUG_FINITEMAPS)/* NB NB NB */
+#define OUTPUTABLE_key , Outputable key
+#else
+#define OUTPUTABLE_key {--}
+#endif
+
+import Maybes
+import Bag ( Bag, foldrBag )
+import Util
+import Outputable
+
+import GLAEXTS
+
+#if ! OMIT_NATIVE_CODEGEN
+# define IF_NCG(a) a
+#else
+# define IF_NCG(a) {--}
+#endif
+
+
+-- SIGH: but we use unboxed "sizes"...
+#if __GLASGOW_HASKELL__
+#define IF_GHC(a,b) a
+#else /* not GHC */
+#define IF_GHC(a,b) b
+#endif /* not GHC */
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The signature of the module}
+%* *
+%************************************************************************
+
+\begin{code}
+-- BUILDING
+emptyFM :: FiniteMap key elt
+unitFM :: key -> elt -> FiniteMap key elt
+listToFM :: (Ord key OUTPUTABLE_key) => [(key,elt)] -> FiniteMap key elt
+ -- In the case of duplicates, the last is taken
+bagToFM :: (Ord key OUTPUTABLE_key) => Bag (key,elt) -> FiniteMap key elt
+ -- In the case of duplicates, who knows which is taken
+
+-- ADDING AND DELETING
+ -- Throws away any previous binding
+ -- In the list case, the items are added starting with the
+ -- first one in the list
+addToFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> elt -> FiniteMap key elt
+addListToFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> [(key,elt)] -> FiniteMap key elt
+
+ -- Combines with previous binding
+ -- The combining fn goes (old -> new -> new)
+addToFM_C :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt)
+ -> FiniteMap key elt -> key -> elt
+ -> FiniteMap key elt
+addListToFM_C :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt)
+ -> FiniteMap key elt -> [(key,elt)]
+ -> FiniteMap key elt
+
+ -- Deletion doesn't complain if you try to delete something
+ -- which isn't there
+delFromFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> FiniteMap key elt
+delListFromFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> [key] -> FiniteMap key elt
+
+-- COMBINING
+ -- Bindings in right argument shadow those in the left
+plusFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+ -- Combines bindings for the same thing with the given function
+plusFM_C :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt)
+ -> FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
+
+minusFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
+ -- (minusFM a1 a2) deletes from a1 any bindings which are bound in a2
+
+intersectFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
+intersectFM_C :: (Ord key OUTPUTABLE_key) => (elt1 -> elt2 -> elt3)
+ -> FiniteMap key elt1 -> FiniteMap key elt2 -> FiniteMap key elt3
+
+-- MAPPING, FOLDING, FILTERING
+foldFM :: (key -> elt -> a -> a) -> a -> FiniteMap key elt -> a
+mapFM :: (key -> elt1 -> elt2) -> FiniteMap key elt1 -> FiniteMap key elt2
+filterFM :: (Ord key OUTPUTABLE_key) => (key -> elt -> Bool)
+ -> FiniteMap key elt -> FiniteMap key elt
+
+
+-- INTERROGATING
+sizeFM :: FiniteMap key elt -> Int
+isEmptyFM :: FiniteMap key elt -> Bool
+
+elemFM :: (Ord key OUTPUTABLE_key) => key -> FiniteMap key elt -> Bool
+lookupFM :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> Maybe elt
+lookupWithDefaultFM
+ :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> elt -> key -> elt
+ -- lookupWithDefaultFM supplies a "default" elt
+ -- to return for an unmapped key
+
+-- LISTIFYING
+fmToList :: FiniteMap key elt -> [(key,elt)]
+keysFM :: FiniteMap key elt -> [key]
+eltsFM :: FiniteMap key elt -> [elt]
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{The @FiniteMap@ data type, and building of same}
+%* *
+%************************************************************************
+
+Invariants about @FiniteMap@:
+\begin{enumerate}
+\item
+all keys in a FiniteMap are distinct
+\item
+all keys in left subtree are $<$ key in Branch and
+all keys in right subtree are $>$ key in Branch
+\item
+size field of a Branch gives number of Branch nodes in the tree
+\item
+size of left subtree is differs from size of right subtree by a
+factor of at most \tr{sIZE_RATIO}
+\end{enumerate}
+
+\begin{code}
+data FiniteMap key elt
+ = EmptyFM
+ | Branch key elt -- Key and elt stored here
+ IF_GHC(Int#,Int{-STRICT-}) -- Size >= 1
+ (FiniteMap key elt) -- Children
+ (FiniteMap key elt)
+\end{code}
+
+\begin{code}
+emptyFM = EmptyFM
+{-
+emptyFM
+ = Branch bottom bottom IF_GHC(0#,0) bottom bottom
+ where
+ bottom = panic "emptyFM"
+-}
+
+-- #define EmptyFM (Branch _ _ IF_GHC(0#,0) _ _)
+
+unitFM key elt = Branch key elt IF_GHC(1#,1) emptyFM emptyFM
+
+listToFM = addListToFM emptyFM
+
+bagToFM = foldrBag (\(k,v) fm -> addToFM fm k v) emptyFM
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Adding to and deleting from @FiniteMaps@}
+%* *
+%************************************************************************
+
+\begin{code}
+addToFM fm key elt = addToFM_C (\ old new -> new) fm key elt
+
+addToFM_C combiner EmptyFM key elt = unitFM key elt
+addToFM_C combiner (Branch key elt size fm_l fm_r) new_key new_elt
+ = case compare new_key key of
+ LT -> mkBalBranch key elt (addToFM_C combiner fm_l new_key new_elt) fm_r
+ GT -> mkBalBranch key elt fm_l (addToFM_C combiner fm_r new_key new_elt)
+ EQ -> Branch new_key (combiner elt new_elt) size fm_l fm_r
+
+addListToFM fm key_elt_pairs = addListToFM_C (\ old new -> new) fm key_elt_pairs
+
+addListToFM_C combiner fm key_elt_pairs
+ = foldl' add fm key_elt_pairs -- foldl adds from the left
+ where
+ add fmap (key,elt) = addToFM_C combiner fmap key elt
+\end{code}
+
+\begin{code}
+delFromFM EmptyFM del_key = emptyFM
+delFromFM (Branch key elt size fm_l fm_r) del_key
+ = case compare del_key key of
+ GT -> mkBalBranch key elt fm_l (delFromFM fm_r del_key)
+ LT -> mkBalBranch key elt (delFromFM fm_l del_key) fm_r
+ EQ -> glueBal fm_l fm_r
+
+delListFromFM fm keys = foldl' delFromFM fm keys
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Combining @FiniteMaps@}
+%* *
+%************************************************************************
+
+\begin{code}
+plusFM_C combiner EmptyFM fm2 = fm2
+plusFM_C combiner fm1 EmptyFM = fm1
+plusFM_C combiner fm1 (Branch split_key elt2 _ left right)
+ = mkVBalBranch split_key new_elt
+ (plusFM_C combiner lts left)
+ (plusFM_C combiner gts right)
+ where
+ lts = splitLT fm1 split_key
+ gts = splitGT fm1 split_key
+ new_elt = case lookupFM fm1 split_key of
+ Nothing -> elt2
+ Just elt1 -> combiner elt1 elt2
+
+-- It's worth doing plusFM specially, because we don't need
+-- to do the lookup in fm1.
+-- FM2 over-rides FM1.
+
+plusFM EmptyFM fm2 = fm2
+plusFM fm1 EmptyFM = fm1
+plusFM fm1 (Branch split_key elt1 _ left right)
+ = mkVBalBranch split_key elt1 (plusFM lts left) (plusFM gts right)
+ where
+ lts = splitLT fm1 split_key
+ gts = splitGT fm1 split_key
+
+minusFM EmptyFM fm2 = emptyFM
+minusFM fm1 EmptyFM = fm1
+minusFM fm1 (Branch split_key elt _ left right)
+ = glueVBal (minusFM lts left) (minusFM gts right)
+ -- The two can be way different, so we need glueVBal
+ where
+ lts = splitLT fm1 split_key -- NB gt and lt, so the equal ones
+ gts = splitGT fm1 split_key -- are not in either.
+
+intersectFM fm1 fm2 = intersectFM_C (\ left right -> right) fm1 fm2
+
+intersectFM_C combiner fm1 EmptyFM = emptyFM
+intersectFM_C combiner EmptyFM fm2 = emptyFM
+intersectFM_C combiner fm1 (Branch split_key elt2 _ left right)
+
+ | maybeToBool maybe_elt1 -- split_elt *is* in intersection
+ = mkVBalBranch split_key (combiner elt1 elt2) (intersectFM_C combiner lts left)
+ (intersectFM_C combiner gts right)
+
+ | otherwise -- split_elt is *not* in intersection
+ = glueVBal (intersectFM_C combiner lts left) (intersectFM_C combiner gts right)
+
+ where
+ lts = splitLT fm1 split_key -- NB gt and lt, so the equal ones
+ gts = splitGT fm1 split_key -- are not in either.
+
+ maybe_elt1 = lookupFM fm1 split_key
+ Just elt1 = maybe_elt1
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Mapping, folding, and filtering with @FiniteMaps@}
+%* *
+%************************************************************************
+
+\begin{code}
+foldFM k z EmptyFM = z
+foldFM k z (Branch key elt _ fm_l fm_r)
+ = foldFM k (k key elt (foldFM k z fm_r)) fm_l
+
+mapFM f EmptyFM = emptyFM
+mapFM f (Branch key elt size fm_l fm_r)
+ = Branch key (f key elt) size (mapFM f fm_l) (mapFM f fm_r)
+
+filterFM p EmptyFM = emptyFM
+filterFM p (Branch key elt _ fm_l fm_r)
+ | p key elt -- Keep the item
+ = mkVBalBranch key elt (filterFM p fm_l) (filterFM p fm_r)
+
+ | otherwise -- Drop the item
+ = glueVBal (filterFM p fm_l) (filterFM p fm_r)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Interrogating @FiniteMaps@}
+%* *
+%************************************************************************
+
+\begin{code}
+--{-# INLINE sizeFM #-}
+sizeFM EmptyFM = 0
+sizeFM (Branch _ _ size _ _) = IF_GHC(I# size, size)
+
+isEmptyFM fm = sizeFM fm == 0
+
+lookupFM EmptyFM key = Nothing
+lookupFM (Branch key elt _ fm_l fm_r) key_to_find
+ = case compare key_to_find key of
+ LT -> lookupFM fm_l key_to_find
+ GT -> lookupFM fm_r key_to_find
+ EQ -> Just elt
+
+key `elemFM` fm
+ = case (lookupFM fm key) of { Nothing -> False; Just elt -> True }
+
+lookupWithDefaultFM fm deflt key
+ = case (lookupFM fm key) of { Nothing -> deflt; Just elt -> elt }
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Listifying @FiniteMaps@}
+%* *
+%************************************************************************
+
+\begin{code}
+fmToList fm = foldFM (\ key elt rest -> (key,elt) : rest) [] fm
+keysFM fm = foldFM (\ key elt rest -> key : rest) [] fm
+eltsFM fm = foldFM (\ key elt rest -> elt : rest) [] fm
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The implementation of balancing}
+%* *
+%************************************************************************
+
+%************************************************************************
+%* *
+\subsubsection{Basic construction of a @FiniteMap@}
+%* *
+%************************************************************************
+
+@mkBranch@ simply gets the size component right. This is the ONLY
+(non-trivial) place the Branch object is built, so the ASSERTion
+recursively checks consistency. (The trivial use of Branch is in
+@unitFM@.)
+
+\begin{code}
+sIZE_RATIO :: Int
+sIZE_RATIO = 5
+
+mkBranch :: (Ord key OUTPUTABLE_key) -- Used for the assertion checking only
+ => Int
+ -> key -> elt
+ -> FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+mkBranch which key elt fm_l fm_r
+ = --ASSERT( left_ok && right_ok && balance_ok )
+#if defined(DEBUG_FINITEMAPS)
+ if not ( left_ok && right_ok && balance_ok ) then
+ pprPanic ("mkBranch:"++show which) (vcat [ppr [left_ok, right_ok, balance_ok],
+ ppr key,
+ ppr fm_l,
+ ppr fm_r])
+ else
+#endif
+ let
+ result = Branch key elt (unbox (1 + left_size + right_size)) fm_l fm_r
+ in
+-- if sizeFM result <= 8 then
+ result
+-- else
+-- pprTrace ("mkBranch:"++(show which)) (ppr result) (
+-- result
+-- )
+ where
+ left_ok = case fm_l of
+ EmptyFM -> True
+ Branch left_key _ _ _ _ -> let
+ biggest_left_key = fst (findMax fm_l)
+ in
+ biggest_left_key < key
+ right_ok = case fm_r of
+ EmptyFM -> True
+ Branch right_key _ _ _ _ -> let
+ smallest_right_key = fst (findMin fm_r)
+ in
+ key < smallest_right_key
+ balance_ok = True -- sigh
+{- LATER:
+ balance_ok
+ = -- Both subtrees have one or no elements...
+ (left_size + right_size <= 1)
+-- NO || left_size == 0 -- ???
+-- NO || right_size == 0 -- ???
+ -- ... or the number of elements in a subtree does not exceed
+ -- sIZE_RATIO times the number of elements in the other subtree
+ || (left_size * sIZE_RATIO >= right_size &&
+ right_size * sIZE_RATIO >= left_size)
+-}
+
+ left_size = sizeFM fm_l
+ right_size = sizeFM fm_r
+
+#ifdef __GLASGOW_HASKELL__
+ unbox :: Int -> Int#
+ unbox (I# size) = size
+#else
+ unbox :: Int -> Int
+ unbox x = x
+#endif
+\end{code}
+
+%************************************************************************
+%* *
+\subsubsection{{\em Balanced} construction of a @FiniteMap@}
+%* *
+%************************************************************************
+
+@mkBalBranch@ rebalances, assuming that the subtrees aren't too far
+out of whack.
+
+\begin{code}
+mkBalBranch :: (Ord key OUTPUTABLE_key)
+ => key -> elt
+ -> FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+mkBalBranch key elt fm_L fm_R
+
+ | size_l + size_r < 2
+ = mkBranch 1{-which-} key elt fm_L fm_R
+
+ | size_r > sIZE_RATIO * size_l -- Right tree too big
+ = case fm_R of
+ Branch _ _ _ fm_rl fm_rr
+ | sizeFM fm_rl < 2 * sizeFM fm_rr -> single_L fm_L fm_R
+ | otherwise -> double_L fm_L fm_R
+ -- Other case impossible
+
+ | size_l > sIZE_RATIO * size_r -- Left tree too big
+ = case fm_L of
+ Branch _ _ _ fm_ll fm_lr
+ | sizeFM fm_lr < 2 * sizeFM fm_ll -> single_R fm_L fm_R
+ | otherwise -> double_R fm_L fm_R
+ -- Other case impossible
+
+ | otherwise -- No imbalance
+ = mkBranch 2{-which-} key elt fm_L fm_R
+
+ where
+ size_l = sizeFM fm_L
+ size_r = sizeFM fm_R
+
+ single_L fm_l (Branch key_r elt_r _ fm_rl fm_rr)
+ = mkBranch 3{-which-} key_r elt_r (mkBranch 4{-which-} key elt fm_l fm_rl) fm_rr
+
+ double_L fm_l (Branch key_r elt_r _ (Branch key_rl elt_rl _ fm_rll fm_rlr) fm_rr)
+ = mkBranch 5{-which-} key_rl elt_rl (mkBranch 6{-which-} key elt fm_l fm_rll)
+ (mkBranch 7{-which-} key_r elt_r fm_rlr fm_rr)
+
+ single_R (Branch key_l elt_l _ fm_ll fm_lr) fm_r
+ = mkBranch 8{-which-} key_l elt_l fm_ll (mkBranch 9{-which-} key elt fm_lr fm_r)
+
+ double_R (Branch key_l elt_l _ fm_ll (Branch key_lr elt_lr _ fm_lrl fm_lrr)) fm_r
+ = mkBranch 10{-which-} key_lr elt_lr (mkBranch 11{-which-} key_l elt_l fm_ll fm_lrl)
+ (mkBranch 12{-which-} key elt fm_lrr fm_r)
+\end{code}
+
+
+\begin{code}
+mkVBalBranch :: (Ord key OUTPUTABLE_key)
+ => key -> elt
+ -> FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+-- Assert: in any call to (mkVBalBranch_C comb key elt l r),
+-- (a) all keys in l are < all keys in r
+-- (b) all keys in l are < key
+-- (c) all keys in r are > key
+
+mkVBalBranch key elt EmptyFM fm_r = addToFM fm_r key elt
+mkVBalBranch key elt fm_l EmptyFM = addToFM fm_l key elt
+
+mkVBalBranch key elt fm_l@(Branch key_l elt_l _ fm_ll fm_lr)
+ fm_r@(Branch key_r elt_r _ fm_rl fm_rr)
+ | sIZE_RATIO * size_l < size_r
+ = mkBalBranch key_r elt_r (mkVBalBranch key elt fm_l fm_rl) fm_rr
+
+ | sIZE_RATIO * size_r < size_l
+ = mkBalBranch key_l elt_l fm_ll (mkVBalBranch key elt fm_lr fm_r)
+
+ | otherwise
+ = mkBranch 13{-which-} key elt fm_l fm_r
+
+ where
+ size_l = sizeFM fm_l
+ size_r = sizeFM fm_r
+\end{code}
+
+%************************************************************************
+%* *
+\subsubsection{Gluing two trees together}
+%* *
+%************************************************************************
+
+@glueBal@ assumes its two arguments aren't too far out of whack, just
+like @mkBalBranch@. But: all keys in first arg are $<$ all keys in
+second.
+
+\begin{code}
+glueBal :: (Ord key OUTPUTABLE_key)
+ => FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+glueBal EmptyFM fm2 = fm2
+glueBal fm1 EmptyFM = fm1
+glueBal fm1 fm2
+ -- The case analysis here (absent in Adams' program) is really to deal
+ -- with the case where fm2 is a singleton. Then deleting the minimum means
+ -- we pass an empty tree to mkBalBranch, which breaks its invariant.
+ | sizeFM fm2 > sizeFM fm1
+ = mkBalBranch mid_key2 mid_elt2 fm1 (deleteMin fm2)
+
+ | otherwise
+ = mkBalBranch mid_key1 mid_elt1 (deleteMax fm1) fm2
+ where
+ (mid_key1, mid_elt1) = findMax fm1
+ (mid_key2, mid_elt2) = findMin fm2
+\end{code}
+
+@glueVBal@ copes with arguments which can be of any size.
+But: all keys in first arg are $<$ all keys in second.
+
+\begin{code}
+glueVBal :: (Ord key OUTPUTABLE_key)
+ => FiniteMap key elt -> FiniteMap key elt
+ -> FiniteMap key elt
+
+glueVBal EmptyFM fm2 = fm2
+glueVBal fm1 EmptyFM = fm1
+glueVBal fm_l@(Branch key_l elt_l _ fm_ll fm_lr)
+ fm_r@(Branch key_r elt_r _ fm_rl fm_rr)
+ | sIZE_RATIO * size_l < size_r
+ = mkBalBranch key_r elt_r (glueVBal fm_l fm_rl) fm_rr
+
+ | sIZE_RATIO * size_r < size_l
+ = mkBalBranch key_l elt_l fm_ll (glueVBal fm_lr fm_r)
+
+ | otherwise -- We now need the same two cases as in glueBal above.
+ = glueBal fm_l fm_r
+ where
+ size_l = sizeFM fm_l
+ size_r = sizeFM fm_r
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Local utilities}
+%* *
+%************************************************************************
+
+\begin{code}
+splitLT, splitGT :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> FiniteMap key elt
+
+-- splitLT fm split_key = fm restricted to keys < split_key
+-- splitGT fm split_key = fm restricted to keys > split_key
+
+splitLT EmptyFM split_key = emptyFM
+splitLT (Branch key elt _ fm_l fm_r) split_key
+ = case compare split_key key of
+ LT -> splitLT fm_l split_key
+ GT -> mkVBalBranch key elt fm_l (splitLT fm_r split_key)
+ EQ -> fm_l
+
+splitGT EmptyFM split_key = emptyFM
+splitGT (Branch key elt _ fm_l fm_r) split_key
+ = case compare split_key key of
+ GT -> splitGT fm_r split_key
+ LT -> mkVBalBranch key elt (splitGT fm_l split_key) fm_r
+ EQ -> fm_r
+
+findMin :: FiniteMap key elt -> (key,elt)
+findMin (Branch key elt _ EmptyFM _) = (key,elt)
+findMin (Branch key elt _ fm_l _) = findMin fm_l
+
+deleteMin :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt
+deleteMin (Branch key elt _ EmptyFM fm_r) = fm_r
+deleteMin (Branch key elt _ fm_l fm_r) = mkBalBranch key elt (deleteMin fm_l) fm_r
+
+findMax :: FiniteMap key elt -> (key,elt)
+findMax (Branch key elt _ _ EmptyFM) = (key,elt)
+findMax (Branch key elt _ _ fm_r) = findMax fm_r
+
+deleteMax :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt
+deleteMax (Branch key elt _ fm_l EmptyFM) = fm_l
+deleteMax (Branch key elt _ fm_l fm_r) = mkBalBranch key elt fm_l (deleteMax fm_r)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Output-ery}
+%* *
+%************************************************************************
+
+\begin{code}
+#if defined(DEBUG_FINITEMAPS)
+
+instance (Outputable key) => Outputable (FiniteMap key elt) where
+ ppr fm = pprX fm
+
+pprX EmptyFM = char '!'
+pprX (Branch key elt sz fm_l fm_r)
+ = parens (hcat [pprX fm_l, space,
+ ppr key, space, int (IF_GHC(I# sz, sz)), space,
+ pprX fm_r])
+#else
+-- and when not debugging the package itself...
+instance (Outputable key, Outputable elt) => Outputable (FiniteMap key elt) where
+ ppr fm = ppr (fmToList fm)
+#endif
+
+#if 0
+instance (Eq key, Eq elt) => Eq (FiniteMap key elt) where
+ fm_1 == fm_2 = (sizeFM fm_1 == sizeFM fm_2) && -- quick test
+ (fmToList fm_1 == fmToList fm_2)
+
+{- NO: not clear what The Right Thing to do is:
+instance (Ord key, Ord elt) => Ord (FiniteMap key elt) where
+ fm_1 <= fm_2 = (sizeFM fm_1 <= sizeFM fm_2) && -- quick test
+ (fmToList fm_1 <= fmToList fm_2)
+-}
+#endif
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Efficiency pragmas for GHC}
+%* *
+%************************************************************************
+
+When the FiniteMap module is used in GHC, we specialise it for
+\tr{Uniques}, for dastardly efficiency reasons.
+
+\begin{code}
+#if 0
+
+#if __GLASGOW_HASKELL__
+
+{-# SPECIALIZE addListToFM
+ :: FiniteMap (FastString, FAST_STRING) elt -> [((FAST_STRING, FAST_STRING),elt)] -> FiniteMap (FAST_STRING, FAST_STRING) elt
+ , FiniteMap RdrName elt -> [(RdrName,elt)] -> FiniteMap RdrName elt
+ IF_NCG(COMMA FiniteMap Reg elt -> [(Reg COMMA elt)] -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE addListToFM_C
+ :: (elt -> elt -> elt) -> FiniteMap TyCon elt -> [(TyCon,elt)] -> FiniteMap TyCon elt
+ , (elt -> elt -> elt) -> FiniteMap FastString elt -> [(FAST_STRING,elt)] -> FiniteMap FAST_STRING elt
+ IF_NCG(COMMA (elt -> elt -> elt) -> FiniteMap Reg elt -> [(Reg COMMA elt)] -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE addToFM
+ :: FiniteMap CLabel elt -> CLabel -> elt -> FiniteMap CLabel elt
+ , FiniteMap FastString elt -> FAST_STRING -> elt -> FiniteMap FAST_STRING elt
+ , FiniteMap (FastString, FAST_STRING) elt -> (FAST_STRING, FAST_STRING) -> elt -> FiniteMap (FAST_STRING, FAST_STRING) elt
+ , FiniteMap RdrName elt -> RdrName -> elt -> FiniteMap RdrName elt
+ IF_NCG(COMMA FiniteMap Reg elt -> Reg -> elt -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE addToFM_C
+ :: (elt -> elt -> elt) -> FiniteMap (RdrName, RdrName) elt -> (RdrName, RdrName) -> elt -> FiniteMap (RdrName, RdrName) elt
+ , (elt -> elt -> elt) -> FiniteMap FastString elt -> FAST_STRING -> elt -> FiniteMap FAST_STRING elt
+ IF_NCG(COMMA (elt -> elt -> elt) -> FiniteMap Reg elt -> Reg -> elt -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE bagToFM
+ :: Bag (FastString,elt) -> FiniteMap FAST_STRING elt
+ #-}
+{-# SPECIALIZE delListFromFM
+ :: FiniteMap RdrName elt -> [RdrName] -> FiniteMap RdrName elt
+ , FiniteMap FastString elt -> [FAST_STRING] -> FiniteMap FAST_STRING elt
+ IF_NCG(COMMA FiniteMap Reg elt -> [Reg] -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE listToFM
+ :: [([Char],elt)] -> FiniteMap [Char] elt
+ , [(FastString,elt)] -> FiniteMap FAST_STRING elt
+ , [((FastString,FAST_STRING),elt)] -> FiniteMap (FAST_STRING, FAST_STRING) elt
+ IF_NCG(COMMA [(Reg COMMA elt)] -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE lookupFM
+ :: FiniteMap CLabel elt -> CLabel -> Maybe elt
+ , FiniteMap [Char] elt -> [Char] -> Maybe elt
+ , FiniteMap FastString elt -> FAST_STRING -> Maybe elt
+ , FiniteMap (FastString,FAST_STRING) elt -> (FAST_STRING,FAST_STRING) -> Maybe elt
+ , FiniteMap RdrName elt -> RdrName -> Maybe elt
+ , FiniteMap (RdrName,RdrName) elt -> (RdrName,RdrName) -> Maybe elt
+ IF_NCG(COMMA FiniteMap Reg elt -> Reg -> Maybe elt)
+ #-}
+{-# SPECIALIZE lookupWithDefaultFM
+ :: FiniteMap FastString elt -> elt -> FAST_STRING -> elt
+ IF_NCG(COMMA FiniteMap Reg elt -> elt -> Reg -> elt)
+ #-}
+{-# SPECIALIZE plusFM
+ :: FiniteMap RdrName elt -> FiniteMap RdrName elt -> FiniteMap RdrName elt
+ , FiniteMap FastString elt -> FiniteMap FAST_STRING elt -> FiniteMap FAST_STRING elt
+ IF_NCG(COMMA FiniteMap Reg elt -> FiniteMap Reg elt -> FiniteMap Reg elt)
+ #-}
+{-# SPECIALIZE plusFM_C
+ :: (elt -> elt -> elt) -> FiniteMap FastString elt -> FiniteMap FAST_STRING elt -> FiniteMap FAST_STRING elt
+ IF_NCG(COMMA (elt -> elt -> elt) -> FiniteMap Reg elt -> FiniteMap Reg elt -> FiniteMap Reg elt)
+ #-}
+
+#endif /* compiling with ghc and have specialiser */
+
+#endif /* 0 */
+\end{code}
projects / ghc-hetmet.git / blobdiff