X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Futils%2FFiniteMap.lhs;h=e301cbca14eb81f37c4a7e9afcbe95cf8f7f261b;hb=aedb94f5f220b5e442b23ecc445fd38c8d9b6ba0;hp=8a041a8cf2055a3a419eb367ce0b12ea2904d9a6;hpb=17b297d97d327620ed6bfab942f8992b2446f1bf;p=ghc-hetmet.git diff --git a/compiler/utils/FiniteMap.lhs b/compiler/utils/FiniteMap.lhs index 8a041a8..e301cbc 100644 --- a/compiler/utils/FiniteMap.lhs +++ b/compiler/utils/FiniteMap.lhs @@ -9,53 +9,45 @@ 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 +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} -{-# OPTIONS_GHC -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/WorkingConventions#Warnings --- for details - module FiniteMap ( - FiniteMap, -- abstract type - - emptyFM, unitFM, listToFM, + -- * Mappings keyed from arbitrary types + FiniteMap, -- abstract type - addToFM, - addToFM_C, - addListToFM, - addListToFM_C, - delFromFM, - delListFromFM, + -- ** Manipulating those mappings + emptyFM, unitFM, listToFM, - plusFM, - plusFM_C, - minusFM, - foldFM, + addToFM, + addToFM_C, + addListToFM, + addListToFM_C, + delFromFM, + delListFromFM, - intersectFM, - intersectFM_C, - mapFM, filterFM, + plusFM, + plusFM_C, + minusFM, + foldFM, - sizeFM, isEmptyFM, elemFM, lookupFM, lookupWithDefaultFM, + intersectFM, + intersectFM_C, + mapFM, filterFM, - fmToList, keysFM, eltsFM + sizeFM, isEmptyFM, elemFM, lookupFM, lookupWithDefaultFM, - , bagToFM + fmToList, keysFM, eltsFM, + bagToFM ) where -#include "HsVersions.h" - #if defined(DEBUG_FINITEMAPS)/* NB NB NB */ #define OUTPUTABLE_key , Outputable key #else @@ -63,8 +55,7 @@ module FiniteMap ( #endif import Maybes -import Bag ( Bag, foldrBag ) -import Util +import Bag ( Bag, foldrBag ) import Outputable #if 0 @@ -86,85 +77,99 @@ import Data.List %************************************************************************ -%* * +%* * \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] +-- BUILDING +emptyFM :: FiniteMap key elt +unitFM :: key -> elt -> FiniteMap key elt +-- | In the case of duplicates keys, the last item is taken +listToFM :: (Ord key OUTPUTABLE_key) => [(key,elt)] -> FiniteMap key elt +-- | In the case of duplicate keys, who knows which item is taken +bagToFM :: (Ord key OUTPUTABLE_key) => Bag (key,elt) -> FiniteMap key elt + +-- ADDING AND DELETING + +-- | Throws away any previous binding +addToFM :: (Ord key OUTPUTABLE_key) + => FiniteMap key elt -> key -> elt -> FiniteMap key elt +-- | Throws away any previous binding, items are added left-to-right +addListToFM :: (Ord key OUTPUTABLE_key) + => FiniteMap key elt -> [(key,elt)] -> FiniteMap key elt + +-- | Combines added item with previous item, if any +addToFM_C :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt) + -> FiniteMap key elt -> key -> elt + -> FiniteMap key elt +-- | Combines added item with previous item, if any, items are added left-to-right +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 +-- | Deletion doesn't complain if you try to delete something which isn't there +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, +-- bindings in right argument shadow those in the left +plusFM_C :: (Ord key OUTPUTABLE_key) + => (elt -> elt -> elt) + -> FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt + +-- | Deletes from the left argument any bindings in the right argument +minusFM :: (Ord key OUTPUTABLE_key) + => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt + +intersectFM :: (Ord key OUTPUTABLE_key) + => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt +-- | Combines bindings for the same thing in the two maps with the given function +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 +-- | Supplies a "default" element in return for an unmapped key +lookupWithDefaultFM :: (Ord key OUTPUTABLE_key) + => FiniteMap key elt -> elt -> key -> elt + +-- 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@: @@ -182,6 +187,7 @@ factor of at most \tr{sIZE_RATIO} \end{enumerate} \begin{code} +-- | A finite mapping from (orderable) key types to elements data FiniteMap key elt = EmptyFM | Branch key elt -- Key and elt stored here @@ -209,22 +215,23 @@ 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 fm key elt = addToFM_C (\ _old new -> new) fm key elt -addToFM_C combiner EmptyFM key elt = unitFM key elt +addToFM_C _ 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 + 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 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 @@ -233,35 +240,35 @@ addListToFM_C combiner fm key_elt_pairs \end{code} \begin{code} -delFromFM EmptyFM del_key = emptyFM -delFromFM (Branch key elt size fm_l fm_r) del_key +delFromFM EmptyFM _ = emptyFM +delFromFM (Branch key elt _ 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 + 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 _ EmptyFM fm2 = fm2 +plusFM_C _ 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) + (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 + Nothing -> elt2 + Just elt1 -> combiner elt1 elt2 -- It's worth doing plusFM specially, because we don't need -- to do the lookup in fm1. @@ -275,110 +282,111 @@ plusFM fm1 (Branch split_key elt1 _ left right) lts = splitLT fm1 split_key gts = splitGT fm1 split_key -minusFM EmptyFM fm2 = emptyFM +minusFM EmptyFM _ = emptyFM minusFM fm1 EmptyFM = fm1 -minusFM fm1 (Branch split_key elt _ left right) +minusFM fm1 (Branch split_key _ _ left right) = glueVBal (minusFM lts left) (minusFM gts right) - -- The two can be way different, so we need glueVBal + -- 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. + 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 fm1 fm2 = intersectFM_C (\ _ right -> right) fm1 fm2 -intersectFM_C combiner fm1 EmptyFM = emptyFM -intersectFM_C combiner EmptyFM fm2 = emptyFM +intersectFM_C _ _ EmptyFM = emptyFM +intersectFM_C _ EmptyFM _ = 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) + | 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) + | 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. + 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 _ 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 _ 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 _ EmptyFM = emptyFM filterFM p (Branch key elt _ fm_l fm_r) - | p key elt -- Keep the item + | p key elt -- Keep the item = mkVBalBranch key elt (filterFM p fm_l) (filterFM p fm_r) - | otherwise -- Drop the item + | 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 EmptyFM = 0 sizeFM (Branch _ _ size _ _) = size isEmptyFM fm = sizeFM fm == 0 -lookupFM EmptyFM key = Nothing +lookupFM EmptyFM _ = 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 + 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 } +key `elemFM` fm = isJust (lookupFM fm key) 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 +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 @@ -390,55 +398,58 @@ recursively checks consistency. (The trivial use of Branch is in 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 :: (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 +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]) + 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 (1 + left_size + right_size) fm_l fm_r + result = Branch key elt (1 + left_size + right_size) fm_l fm_r in -- if sizeFM result <= 8 then - result + result -- else --- pprTrace ("mkBranch:"++(show which)) (ppr result) ( --- result --- ) +-- pprTrace ("mkBranch:"++(show which)) (ppr result) ( +-- result +-- ) where +#if defined(DEBUG_FINITEMAPS) left_ok = case fm_l of - EmptyFM -> True - Branch left_key _ _ _ _ -> let - biggest_left_key = fst (findMax fm_l) - in - biggest_left_key < key + EmptyFM -> True + Branch _ _ _ _ _ -> 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 + EmptyFM -> True + Branch _ _ _ _ _ -> let + smallest_right_key = fst (findMin fm_r) + in + key < smallest_right_key balance_ok = True -- sigh +#endif {- 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 + 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) + right_size * sIZE_RATIO >= left_size) -} left_size = sizeFM fm_l @@ -446,9 +457,9 @@ mkBranch which key elt fm_l fm_r \end{code} %************************************************************************ -%* * +%* * \subsubsection{{\em Balanced} construction of a @FiniteMap@} -%* * +%* * %************************************************************************ @mkBalBranch@ rebalances, assuming that the subtrees aren't too far @@ -456,30 +467,29 @@ out of whack. \begin{code} mkBalBranch :: (Ord key OUTPUTABLE_key) - => key -> elt - -> FiniteMap key elt -> FiniteMap key elt - -> FiniteMap key elt + => 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 + | 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 + 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 + _ -> panic "mkBalBranch: impossible case 1" - | size_l > sIZE_RATIO * size_r -- Left tree too big + | 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 + 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 + _ -> panic "mkBalBranch: impossible case 2" + | otherwise -- No imbalance = mkBranch 2{-which-} key elt fm_L fm_R where @@ -487,37 +497,44 @@ mkBalBranch key elt fm_L fm_R 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 + = mkBranch 3{-which-} key_r elt_r (mkBranch 4{-which-} key elt fm_l fm_rl) fm_rr + single_L _ _ = panic "mkBalBranch: impossible case 3" 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) + = 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) + double_L _ _ = panic "mkBalBranch: impossible case 4" 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) + = mkBranch 8{-which-} key_l elt_l fm_ll + (mkBranch 9{-which-} key elt fm_lr fm_r) + single_R _ _ = panic "mkBalBranch: impossible case 5" 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) + = 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) + double_R _ _ = panic "mkBalBranch: impossible case 6" \end{code} \begin{code} mkVBalBranch :: (Ord key OUTPUTABLE_key) - => key -> elt - -> FiniteMap key elt -> FiniteMap key elt - -> FiniteMap key elt + => 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 +-- (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) + 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 @@ -533,9 +550,9 @@ mkVBalBranch key elt fm_l@(Branch key_l elt_l _ fm_ll fm_lr) \end{code} %************************************************************************ -%* * +%* * \subsubsection{Gluing two trees together} -%* * +%* * %************************************************************************ @glueBal@ assumes its two arguments aren't too far out of whack, just @@ -544,15 +561,15 @@ second. \begin{code} glueBal :: (Ord key OUTPUTABLE_key) - => FiniteMap key elt -> FiniteMap key elt - -> FiniteMap key elt + => 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. + -- 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) @@ -568,20 +585,20 @@ 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 + => 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) + 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. + | otherwise -- We now need the same two cases as in glueBal above. = glueBal fm_l fm_r where size_l = sizeFM fm_l @@ -589,9 +606,9 @@ glueVBal fm_l@(Branch key_l elt_l _ fm_ll fm_lr) \end{code} %************************************************************************ -%* * +%* * \subsection{Local utilities} -%* * +%* * %************************************************************************ \begin{code} @@ -600,41 +617,46 @@ splitLT, splitGT :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> Fini -- 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 EmptyFM _ = 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 + 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 EmptyFM _ = 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 + 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 +findMin (Branch key elt _ EmptyFM _) = (key, elt) +findMin (Branch _ _ _ fm_l _) = findMin fm_l +findMin EmptyFM = panic "findMin: Empty" 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 +deleteMin (Branch _ _ _ EmptyFM fm_r) = fm_r +deleteMin (Branch key elt _ fm_l fm_r) + = mkBalBranch key elt (deleteMin fm_l) fm_r +deleteMin EmptyFM = panic "deleteMin: Empty" -findMax :: FiniteMap key elt -> (key,elt) -findMax (Branch key elt _ _ EmptyFM) = (key,elt) -findMax (Branch key elt _ _ fm_r) = findMax fm_r +findMax :: FiniteMap key elt -> (key, elt) +findMax (Branch key elt _ _ EmptyFM) = (key, elt) +findMax (Branch _ _ _ _ fm_r) = findMax fm_r +findMax EmptyFM = panic "findMax: Empty" deleteMax :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt -deleteMax (Branch key elt _ fm_l EmptyFM) = fm_l +deleteMax (Branch _ _ _ fm_l EmptyFM) = fm_l deleteMax (Branch key elt _ fm_l fm_r) = mkBalBranch key elt fm_l (deleteMax fm_r) +deleteMax EmptyFM = panic "deleteMax: Empty" \end{code} %************************************************************************ -%* * +%* * \subsection{Output-ery} -%* * +%* * %************************************************************************ \begin{code} @@ -646,8 +668,8 @@ instance (Outputable key) => Outputable (FiniteMap key elt) where pprX EmptyFM = char '!' pprX (Branch key elt sz fm_l fm_r) = parens (hcat [pprX fm_l, space, - ppr key, space, int sz, space, - pprX fm_r]) + ppr key, space, int sz, space, + pprX fm_r]) #else -- and when not debugging the package itself... instance (Outputable key, Outputable elt) => Outputable (FiniteMap key elt) where @@ -657,20 +679,20 @@ instance (Outputable key, Outputable elt) => Outputable (FiniteMap key elt) wher #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) + (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) + (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 @@ -679,64 +701,64 @@ When the FiniteMap module is used in GHC, we specialise it for \begin{code} #if 0 -#if __GLASGOW_HASKELL__ +#ifdef __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 + :: 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 + :: (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 + :: 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 + :: (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 + :: 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 + :: 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 + :: [([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 + :: 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 + :: 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 + :: 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 + :: (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) #-}