\begin{code}
module MkIface (
- startIface, endIface,
- ifaceMain,
- ifaceDecls
+ startIface, endIface, ifaceDecls
) where
#include "HsVersions.h"
hClose, hPutStrLn, IOMode(..) )
import HsSyn
-import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..),
- StrictnessMark(..)
- )
+import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..) )
import RnMonad
import RnEnv ( availName )
import TcInstUtil ( InstInfo(..) )
-import WorkWrap ( getWorkerIdAndCons )
import CmdLineOpts
-import Id ( Id, idType, idInfo, omitIfaceSigForId,
+import Id ( Id, idType, idInfo, omitIfaceSigForId, isUserExportedId,
getIdSpecialisation
)
import Var ( isId )
import VarSet
-import DataCon ( dataConSig, dataConFieldLabels, dataConStrictMarks )
-import IdInfo ( IdInfo, StrictnessInfo, ArityInfo, InlinePragInfo(..), inlinePragInfo,
- arityInfo, ppArityInfo,
- strictnessInfo, ppStrictnessInfo,
- cafInfo, ppCafInfo,
- workerExists, isBottomingStrictness
+import DataCon ( StrictnessMark(..), dataConSig, dataConFieldLabels, dataConStrictMarks )
+import IdInfo ( IdInfo, StrictnessInfo(..), ArityInfo, InlinePragInfo(..), inlinePragInfo,
+ arityInfo, ppArityInfo, arityLowerBound,
+ strictnessInfo, ppStrictnessInfo, isBottomingStrictness,
+ cafInfo, ppCafInfo, specInfo,
+ cprInfo, ppCprInfo, pprInlinePragInfo,
+ occInfo, OccInfo(..),
+ workerExists, workerInfo, ppWorkerInfo
)
-import CoreSyn ( CoreExpr, CoreBind, Bind(..) )
-import CoreUtils ( exprSomeFreeVars )
-import CoreUnfold ( calcUnfoldingGuidance, UnfoldingGuidance(..),
- Unfolding, okToUnfoldInHiFile )
+import CoreSyn ( CoreExpr, CoreBind, Bind(..), rulesRules, rulesRhsFreeVars )
+import CoreFVs ( exprSomeFreeVars, ruleSomeLhsFreeVars, ruleSomeFreeVars )
+import CoreUnfold ( calcUnfoldingGuidance, okToUnfoldInHiFile, couldBeSmallEnoughToInline )
+import Module ( moduleString, pprModule, pprModuleName )
import Name ( isLocallyDefined, isWiredInName, nameRdrName, nameModule,
- isExported,
Name, NamedThing(..)
)
-import OccName ( OccName, pprOccName, moduleString, pprModule, pprModuleBoot )
+import OccName ( OccName, pprOccName )
import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
tyConTheta, tyConTyVars, tyConDataCons
)
-import Class ( Class, classBigSig )
-import SpecEnv ( specEnvToList )
+import Class ( Class, classExtraBigSig )
import FieldLabel ( fieldLabelName, fieldLabelType )
import Type ( mkSigmaTy, splitSigmaTy, mkDictTy, tidyTopType, deNoteType,
Type, ThetaType
)
import PprType
-import PprCore ( pprIfaceUnfolding )
+import PprCore ( pprIfaceUnfolding, pprCoreRule )
+import FunDeps ( pprFundeps )
+import Rules ( pprProtoCoreRule, ProtoCoreRule(..) )
import Bag ( bagToList, isEmptyBag )
import Maybes ( catMaybes, maybeToBool )
import UniqFM ( lookupUFM, listToUFM )
import UniqSet ( uniqSetToList )
import Util ( sortLt, mapAccumL )
+import Bag
import Outputable
\end{code}
to the handle provided by @startIface@.
\begin{code}
-startIface :: Module
+startIface :: Module -> InterfaceDetails
-> IO (Maybe Handle) -- Nothing <=> don't do an interface
-ifaceMain :: Maybe Handle
- -> InterfaceDetails
- -> IO ()
-
-
ifaceDecls :: Maybe Handle
-> [TyCon] -> [Class]
-> Bag InstInfo
-> [Id] -- Ids used at code-gen time; they have better pragma info!
-> [CoreBind] -- In dependency order, later depend on earlier
+ -> [ProtoCoreRule] -- Rules
-> IO ()
endIface :: Maybe Handle -> IO ()
\end{code}
\begin{code}
-startIface mod
+startIface mod (has_orphans, import_usages, ExportEnv avails fixities _)
= case opt_ProduceHi of
- Nothing -> return Nothing -- not producing any .hi file
- Just fn -> do
+ Nothing -> return Nothing ; -- not producing any .hi file
+
+ Just fn -> do
if_hdl <- openFile fn WriteMode
- hPutStr if_hdl ("__interface " ++ moduleString mod ++ ' ':show (opt_HiVersion :: Int))
- hPutStrLn if_hdl " where"
+ hPutStr if_hdl ("__interface " ++ moduleString mod)
+ hPutStr if_hdl (' ' : show (opt_HiVersion :: Int) ++ orphan_indicator)
+ hPutStrLn if_hdl " where"
+ ifaceExports if_hdl avails
+ ifaceImports if_hdl import_usages
+ ifaceFixities if_hdl fixities
return (Just if_hdl)
+ where
+ orphan_indicator | has_orphans = " !"
+ | otherwise = ""
endIface Nothing = return ()
endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
\begin{code}
-ifaceMain Nothing iface_stuff = return ()
-ifaceMain (Just if_hdl)
- (import_usages, ExportEnv avails fixities, instance_modules)
- = do
- ifaceImports if_hdl import_usages
- ifaceInstanceModules if_hdl instance_modules
- ifaceExports if_hdl avails
- ifaceFixities if_hdl fixities
- return ()
-
-ifaceDecls Nothing tycons classes inst_info final_ids simplified = return ()
+ifaceDecls Nothing tycons classes inst_info final_ids simplified rules = return ()
ifaceDecls (Just hdl)
tycons classes
inst_infos
final_ids binds
+ orphan_rules -- Rules defined locally for an Id that is *not* defined locally
| null_decls = return ()
-- You could have a module with just (re-)exports/instances in it
| otherwise
= ifaceClasses hdl classes >>
- ifaceInstances hdl inst_infos >>= \ needed_ids ->
+ ifaceInstances hdl inst_infos >>= \ inst_ids ->
ifaceTyCons hdl tycons >>
- ifaceBinds hdl needed_ids final_ids binds >>
+ ifaceBinds hdl (inst_ids `unionVarSet` orphan_rule_ids)
+ final_ids binds >>= \ emitted_ids ->
+ ifaceRules hdl orphan_rules emitted_ids >>
return ()
where
+ orphan_rule_ids = unionVarSets [ ruleSomeFreeVars interestingId rule
+ | ProtoCoreRule _ _ rule <- orphan_rules]
+
null_decls = null binds &&
null tycons &&
null classes &&
- isEmptyBag inst_infos
+ isEmptyBag inst_infos &&
+ null orphan_rules
\end{code}
\begin{code}
ifaceImports if_hdl import_usages
= hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
where
- upp_uses (m, mv, whats_imported)
- = ptext SLIT("import ") <>
- hsep [pprModule m, pprModuleBoot m, int mv, dcolon,
+ upp_uses (m, mv, has_orphans, whats_imported)
+ = hsep [ptext SLIT("import"), pprModuleName m,
+ int mv, pp_orphan,
upp_import_versions whats_imported
] <> semi
+ where
+ pp_orphan | has_orphans = ptext SLIT("!")
+ | otherwise = empty
-- Importing the whole module is indicated by an empty list
upp_import_versions Everything = empty
-- For imported versions we do print the version number
upp_import_versions (Specifically nvs)
- = hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
-
-ifaceInstanceModules if_hdl [] = return ()
-ifaceInstanceModules if_hdl imods
- = let sorted = sortLt (<) imods
- lines = map (\m -> ptext SLIT("__instimport ") <> pprModule m <>
- ptext SLIT(" ;")) sorted
+ = dcolon <+> hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
+
+ifaceModuleDeps if_hdl [] = return ()
+ifaceModuleDeps if_hdl mod_deps
+ = let
+ lines = map ppr_mod_dep mod_deps
+ ppr_mod_dep (mod, contains_orphans)
+ | contains_orphans = pprModuleName mod <+> ptext SLIT("!")
+ | otherwise = pprModuleName mod
in
- printForIface if_hdl (vcat lines) >>
+ printForIface if_hdl (ptext SLIT("__depends") <+> vcat lines <> ptext SLIT(" ;")) >>
hPutStr if_hdl "\n"
ifaceExports if_hdl [] = return ()
do_one_module :: (Module, [AvailInfo]) -> SDoc
do_one_module (mod_name, avails@(avail1:_))
= ptext SLIT("__export ") <>
- hsep [pprModuleBoot (nameModule (availName avail1)),
- pprModule mod_name,
+ hsep [pprModule mod_name,
hsep (map upp_avail (sortLt lt_avail avails))
] <> semi
ifaceFixities if_hdl [] = return ()
ifaceFixities if_hdl fixities
= hPutCol if_hdl upp_fixity fixities
-\end{code}
+
+ifaceRules if_hdl rules emitted
+ | null orphan_rule_pretties && null local_id_pretties
+ = return ()
+ | otherwise
+ = do printForIface if_hdl (vcat [
+ ptext SLIT("{-## __R"),
+
+ vcat orphan_rule_pretties,
+
+ vcat local_id_pretties,
+
+ ptext SLIT("##-}")
+ ])
+
+ return ()
+ where
+ orphan_rule_pretties = [ pprCoreRule (Just fn) rule <+> semi
+ | ProtoCoreRule _ fn rule <- rules
+ ]
+ local_id_pretties = [ pprCoreRule (Just fn) rule <+> semi
+ | fn <- varSetElems emitted,
+ rule <- rulesRules (getIdSpecialisation fn),
+ all (`elemVarSet` emitted) (varSetElems (ruleSomeLhsFreeVars interestingId rule))
+ -- Spit out a rule only if all its lhs free vars are eemitted
+ ]
+\end{code}
%************************************************************************
%* *
-> Bool -- True <=> recursive, so don't print unfolding
-> Id
-> CoreExpr -- The Id's right hand side
- -> Maybe (SDoc, IdSet) -- The emitted stuff, plus a possibly-augmented set of needed Ids
+ -> Maybe (SDoc, IdSet) -- The emitted stuff, plus any *extra* needed Ids
ifaceId get_idinfo needed_ids is_rec id rhs
| not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
- (isExported id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
+ (isUserExportedId id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
= Nothing -- Well, that was easy!
ifaceId get_idinfo needed_ids is_rec id rhs
- = Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
+ = ASSERT2( arity_matches_strictness, ppr id )
+ Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
where
- idinfo = get_idinfo id
- inline_pragma = inlinePragInfo idinfo
+ core_idinfo = idInfo id
+ stg_idinfo = get_idinfo id
ty_pretty = pprType (idType id)
sig_pretty = hsep [ppr (getOccName id), dcolon, ty_pretty]
| otherwise = hsep [ptext SLIT("{-##"),
arity_pretty,
caf_pretty,
- strict_pretty,
+ cpr_pretty,
+ strict_pretty,
+ wrkr_pretty,
unfold_pretty,
- spec_pretty,
ptext SLIT("##-}")]
------------ Arity --------------
- arity_pretty = ppArityInfo (arityInfo idinfo)
+ arity_info = arityInfo stg_idinfo
+ arity_pretty = ppArityInfo arity_info
------------ Caf Info --------------
- caf_pretty = ppCafInfo (cafInfo idinfo)
+ caf_pretty = ppCafInfo (cafInfo stg_idinfo)
+
+ ------------ CPR Info --------------
+ cpr_pretty = ppCprInfo (cprInfo core_idinfo)
------------ Strictness --------------
- strict_info = strictnessInfo idinfo
- has_worker = workerExists strict_info
+ strict_info = strictnessInfo core_idinfo
bottoming_fn = isBottomingStrictness strict_info
- strict_pretty = ppStrictnessInfo strict_info <+> wrkr_pretty
+ strict_pretty = ppStrictnessInfo strict_info
- wrkr_pretty | not has_worker = empty
- | null con_list = ppr work_id
- | otherwise = ppr work_id <+>
- braces (hsep (map ppr con_list))
+ ------------ Worker --------------
+ work_info = workerInfo core_idinfo
+ has_worker = workerExists work_info
+ wrkr_pretty = ppWorkerInfo work_info
+ Just work_id = work_info
- (work_id, wrapper_cons) = getWorkerIdAndCons id rhs
- con_list = uniqSetToList wrapper_cons
-
- ------------ Unfolding --------------
- unfold_pretty | show_unfold = unfold_herald <+> pprIfaceUnfolding rhs
- | otherwise = empty
- show_unfold = not has_worker && -- Not unnecessary
- not bottoming_fn && -- Not necessary
- unfolding_needed -- Not dangerous
+ ------------ Occ info --------------
+ loop_breaker = case occInfo core_idinfo of
+ IAmALoopBreaker -> True
+ other -> False
- unfolding_needed = case inline_pragma of
- IMustBeINLINEd -> definitely_ok_to_unfold
- IWantToBeINLINEd -> definitely_ok_to_unfold
- NoInlinePragInfo -> rhs_is_small
- other -> False
+ ------------ Unfolding --------------
+ inline_pragma = inlinePragInfo core_idinfo
+ dont_inline = case inline_pragma of
+ IMustNotBeINLINEd False Nothing -> True -- Unconditional NOINLINE
+ other -> False
- unfold_herald = case inline_pragma of
- NoInlinePragInfo -> ptext SLIT("__u")
- other -> ppr inline_pragma
+ unfold_pretty | show_unfold = ptext SLIT("__U") <> pprInlinePragInfo inline_pragma <+> pprIfaceUnfolding rhs
+ | otherwise = empty
- rhs_is_small = case calcUnfoldingGuidance opt_InterfaceUnfoldThreshold rhs of
- UnfoldNever -> False -- Too big
- other -> definitely_ok_to_unfold -- Small enough
+ show_unfold = not has_worker && -- Not unnecessary
+ not bottoming_fn && -- Not necessary
+ not dont_inline &&
+ not loop_breaker &&
+ rhs_is_small && -- Small enough
+ okToUnfoldInHiFile rhs -- No casms etc
- definitely_ok_to_unfold = okToUnfoldInHiFile rhs
+ rhs_is_small = couldBeSmallEnoughToInline (calcUnfoldingGuidance opt_UF_HiFileThreshold rhs)
------------ Specialisations --------------
- spec_list = specEnvToList (getIdSpecialisation id)
- spec_pretty = hsep (map pp_spec spec_list)
- pp_spec (tyvars, tys, rhs) = hsep [ptext SLIT("__P"),
- if null tyvars then ptext SLIT("[ ]")
- else brackets (interppSP tyvars),
- -- The lexer interprets "[]" as a CONID. Sigh.
- hsep (map pprParendType tys),
- ptext SLIT("="),
- pprIfaceUnfolding rhs
- ]
+ spec_info = specInfo core_idinfo
------------ Extra free Ids --------------
- new_needed_ids = (needed_ids `minusVarSet` unitVarSet id) `unionVarSet`
- extra_ids
-
- extra_ids | opt_OmitInterfacePragmas = emptyVarSet
- | otherwise = worker_ids `unionVarSet`
- unfold_ids `unionVarSet`
- spec_ids
+ new_needed_ids | opt_OmitInterfacePragmas = emptyVarSet
+ | otherwise = worker_ids `unionVarSet`
+ unfold_ids `unionVarSet`
+ spec_ids
- worker_ids | has_worker && interesting work_id = unitVarSet work_id
+ worker_ids | has_worker && interestingId work_id = unitVarSet work_id
-- Conceivably, the worker might come from
-- another module
| otherwise = emptyVarSet
- spec_ids = foldr add emptyVarSet spec_list
- where
- add (_, _, rhs) = unionVarSet (find_fvs rhs)
+ spec_ids = filterVarSet interestingId (rulesRhsFreeVars spec_info)
unfold_ids | show_unfold = find_fvs rhs
| otherwise = emptyVarSet
- find_fvs expr = free_vars
- where
- free_vars = exprSomeFreeVars interesting expr
-
- interesting id = isId id && isLocallyDefined id &&
- not (omitIfaceSigForId id)
+ find_fvs expr = exprSomeFreeVars interestingId expr
+
+ ------------ Sanity checking --------------
+ -- The arity of a wrapper function should match its strictness,
+ -- or else an importing module will get very confused indeed.
+ -- [later: actually all that is necessary is for strictness to exceed arity]
+ arity_matches_strictness
+ = not has_worker ||
+ case strict_info of
+ StrictnessInfo ds _ -> length ds >= arityLowerBound arity_info
+ other -> True
+
+interestingId id = isId id && isLocallyDefined id &&
+ not (omitIfaceSigForId id)
\end{code}
\begin{code}
-> IdSet -- These Ids are needed already
-> [Id] -- Ids used at code-gen time; they have better pragma info!
-> [CoreBind] -- In dependency order, later depend on earlier
- -> IO ()
+ -> IO IdSet -- Set of Ids actually spat out
ifaceBinds hdl needed_ids final_ids binds
- = mapIO (printForIface hdl) pretties >>
- hPutStr hdl "\n"
+ = mapIO (printForIface hdl) (bagToList pretties) >>
+ hPutStr hdl "\n" >>
+ return emitted
where
final_id_map = listToUFM [(id,id) | id <- final_ids]
get_idinfo id = case lookupUFM final_id_map id of
Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
idInfo id
- pretties = go needed_ids (reverse binds) -- Reverse so that later things will
- -- provoke earlier ones to be emitted
- go needed [] = if not (isEmptyVarSet needed) then
- pprTrace "ifaceBinds: free vars:"
- (sep (map ppr (varSetElems needed))) $
- []
- else
- []
+ (pretties, emitted) = go needed_ids (reverse binds) emptyBag emptyVarSet
+ -- Reverse so that later things will
+ -- provoke earlier ones to be emitted
+ go needed [] pretties emitted
+ | not (isEmptyVarSet needed) = pprTrace "ifaceBinds: free vars:"
+ (sep (map ppr (varSetElems needed)))
+ (pretties, emitted)
+ | otherwise = (pretties, emitted)
- go needed (NonRec id rhs : binds)
+ go needed (NonRec id rhs : binds) pretties emitted
= case ifaceId get_idinfo needed False id rhs of
- Nothing -> go needed binds
- Just (pretty, needed') -> pretty : go needed' binds
+ Nothing -> go needed binds pretties emitted
+ Just (pretty, extras) -> let
+ needed' = (needed `unionVarSet` extras) `delVarSet` id
+ -- 'extras' can include the Id itself via a rule
+ emitted' = emitted `extendVarSet` id
+ in
+ go needed' binds (pretty `consBag` pretties) emitted'
-- Recursive groups are a bit more of a pain. We may only need one to
-- start with, but it may call out the next one, and so on. So we
-- have to look for a fixed point.
- go needed (Rec pairs : binds)
- = pretties ++ go needed'' binds
+ go needed (Rec pairs : binds) pretties emitted
+ = go needed' binds pretties' emitted'
where
- (needed', pretties) = go_rec needed pairs
- needed'' = needed' `minusVarSet` mkVarSet (map fst pairs)
- -- Later ones may spuriously cause earlier ones to be "needed" again
+ (new_pretties, new_emitted, extras) = go_rec needed pairs
+ pretties' = new_pretties `unionBags` pretties
+ needed' = (needed `unionVarSet` extras) `minusVarSet` mkVarSet (map fst pairs)
+ emitted' = emitted `unionVarSet` new_emitted
- go_rec :: IdSet -> [(Id,CoreExpr)] -> (IdSet, [SDoc])
+ go_rec :: IdSet -> [(Id,CoreExpr)] -> (Bag SDoc, IdSet, IdSet)
go_rec needed pairs
- | null pretties = (needed, [])
- | otherwise = (final_needed, more_pretties ++ pretties)
+ | null pretties = (emptyBag, emptyVarSet, emptyVarSet)
+ | otherwise = (more_pretties `unionBags` listToBag pretties,
+ more_emitted `unionVarSet` mkVarSet emitted,
+ more_extras `unionVarSet` extras)
where
- reduced_pairs = [pair | (pair,Nothing) <- pairs `zip` maybes]
- pretties = catMaybes maybes
- (needed', maybes) = mapAccumL do_one needed pairs
- (final_needed, more_pretties) = go_rec needed' reduced_pairs
-
- do_one needed (id,rhs) = case ifaceId get_idinfo needed True id rhs of
- Nothing -> (needed, Nothing)
- Just (pretty, needed') -> (needed', Just pretty)
+ maybes = map do_one pairs
+ emitted = [id | ((id,_), Just _) <- pairs `zip` maybes]
+ reduced_pairs = [pair | (pair, Nothing) <- pairs `zip` maybes]
+ (pretties, extras_s) = unzip (catMaybes maybes)
+ extras = unionVarSets extras_s
+ (more_pretties, more_emitted, more_extras) = go_rec extras reduced_pairs
+
+ do_one (id,rhs) = ifaceId get_idinfo needed True id rhs
\end{code}
ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
- ppr_strict_mark NotMarkedStrict = empty
- ppr_strict_mark MarkedStrict = ptext SLIT("! ")
- -- The extra space helps the lexical analyser that lexes
- -- interface files; it doesn't make the rigid operator/identifier
- -- distinction, so "!a" is a valid identifier so far as it is concerned
+ ppr_strict_mark NotMarkedStrict = empty
+ ppr_strict_mark (MarkedUnboxed _ _) = ptext SLIT("! ! ")
+ ppr_strict_mark MarkedStrict = ptext SLIT("! ")
ppr_field (strict_mark, field_label)
= hsep [ ppr (fieldLabelName field_label),
ppr_decl_context sc_theta,
ppr clas, -- Print the name
pprTyVarBndrs clas_tyvars,
+ pprFundeps clas_fds,
pp_ops,
semi
]
where
- (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
+ (clas_tyvars, clas_fds, sc_theta, _, op_stuff) = classExtraBigSig clas
- pp_ops | null sel_ids = empty
- | otherwise = hsep [ptext SLIT("where"),
- braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
- ]
+ pp_ops | null op_stuff = empty
+ | otherwise = hsep [ptext SLIT("where"),
+ braces (hsep (punctuate semi (map ppr_classop op_stuff)))
+ ]
- ppr_classop sel_id maybe_defm
+ ppr_classop (sel_id, dm_id, explicit_dm)
= ASSERT( sel_tyvars == clas_tyvars)
hsep [ppr (getOccName sel_id),
- if maybeToBool maybe_defm then equals else empty,
+ if explicit_dm then equals else empty,
dcolon,
ppr op_ty
]
ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
-pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
+pprIfaceTheta [] = empty
+pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
\end{code}
%************************************************************************
%************************************************************************
%* *
-\subsection{Comparisons
+\subsection{Comparisons}
%* *
%************************************************************************
lt_lexical a1 a2 = getName a1 `lt_name` getName a2
lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
-lt_imp_vers (m1,_,_) (m2,_,_) = m1 < m2
+lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
sort_versions vs = sortLt lt_vers vs
projects / ghc-hetmet.git / blobdiff