{- |

Module : $Header$

Copyright : (c) Till Mossakowski, Uni Bremen 2002-2006

License : similar to LGPL, see HetCATS/LICENSE.txt or LIZENZ.txt

Maintainer : till@tzi.de

Stability : provisional

Portability : non-portable(Logic)

Central data structure for development graphs.

Follows Sect. IV:4.2 of the CASL Reference Manual.

-}

{-

References:

T. Mossakowski, S. Autexier and D. Hutter:

Extending Development Graphs With Hiding.

H. Hussmann (ed.): Fundamental Approaches to Software Engineering 2001,

Lecture Notes in Computer Science 2029, p. 269-283,

Springer-Verlag 2001.

T. Mossakowski, S. Autexier, D. Hutter, P. Hoffman:

CASL Proof calculus. In: CASL reference manual, part IV.

Available from http://www.cofi.info

todo:

Integrate stuff from Saarbr�cken

Should AS be stored in GloblaContext as well?

simplifyTh should be removed from instance Pretty G_theory

-}

module Static.DevGraph where

import Logic.Logic

import Logic.Grothendieck

import Logic.Comorphism

import Logic.Prover

import Logic.Coerce

import Syntax.AS_Library

import Data.Graph.Inductive.Graph as Graph

import qualified Common.Lib.Graph as Tree

import qualified Common.Lib.Map as Map

import qualified Common.OrderedMap as OMap

import Common.AS_Annotation

import Common.GlobalAnnotations

import Common.Id

import Common.Doc

import Common.DocUtils

import Common.Result

import Common.DynamicUtils

import Control.Monad (foldM)

import Control.Exception

getNewNode :: Tree.Gr a b -> Node

getNewNode g = case newNodes 1 g of

[n] -> n

_ -> error "Static.DevGraph.getNewNode"

-- * Types for structured specification analysis

-- ??? Some info about the theorems already proved for a node

-- should be added

-- or should it be kept separately?

-- what about open theorems of a node???

-- | name of a node in a DG; auxiliary nodes may have extension string

-- | and non-zero number (for these, names are usually hidden)

type NODE_NAME = (SIMPLE_ID, String, Int)

-- | node inscriptions in development graphs

data DGNodeLab =

DGNode {

dgn_name :: NODE_NAME, -- name in the input language

dgn_theory :: G_theory, -- local theory

dgn_nf :: Maybe Node, -- normal form, for Theorem-Hide-Shift

dgn_sigma :: Maybe GMorphism, -- inclusion of signature into nf signature

dgn_origin :: DGOrigin, -- origin in input language

dgn_cons :: Conservativity,

dgn_cons_status :: ThmLinkStatus

}

| DGRef { -- reference to node in a different DG

dgn_name :: NODE_NAME, -- new name of node (in current DG)

dgn_libname :: LIB_NAME, -- pointer to DG where ref'd node resides

dgn_node :: Node, -- pointer to ref'd node

dgn_theory :: G_theory, -- local proof goals

dgn_nf :: Maybe Node, -- normal form, for Theorem-Hide-Shift

dgn_sigma :: Maybe GMorphism -- inclusion of signature into nf signature

} deriving (Show, Eq)

dgn_sign :: DGNodeLab -> G_sign

dgn_sign dn = case dgn_theory dn of

G_theory lid sig _ -> G_sign lid sig

isInternalNode :: DGNodeLab -> Bool

isInternalNode (DGNode n _ _ _ _ _ _) = isInternal n

isInternalNode _ = False

isRefNode :: DGNodeLab -> Bool

isRefNode (DGNode _ _ _ _ _ _ _) = False

isRefNode _ = True

-- gets the name of a development graph node as a string

getDGNodeName :: DGNodeLab -> String

getDGNodeName dgn = showName $ dgn_name dgn

emptyNodeName :: NODE_NAME

emptyNodeName = (mkSimpleId "","",0)

showInt :: Int -> String

showInt i = if i==0 then "" else show i

showName :: NODE_NAME -> String

showName (n,s,i) = show n ++ if ext=="" then "" else "_"++ext

where ext = s ++ showInt i

makeName :: SIMPLE_ID -> NODE_NAME

makeName n = (n,"",0)

getName :: NODE_NAME -> SIMPLE_ID

getName (n,_,_) = n

makeMaybeName :: Maybe SIMPLE_ID -> NODE_NAME

makeMaybeName Nothing = emptyNodeName

makeMaybeName (Just n) = makeName n

inc :: NODE_NAME -> NODE_NAME

inc (n,s,i) = (n,s,i+1)

isInternal :: NODE_NAME -> Bool

isInternal (_,s,i) = (i/=0) || s/=""

extName :: String -> NODE_NAME -> NODE_NAME

extName s (n,s1,i) = (n,s1++showInt i++s,0)

isDGRef :: DGNodeLab -> Bool

isDGRef (DGNode _ _ _ _ _ _ _) = False

isDGRef (DGRef _ _ _ _ _ _) = True

hasOpenGoals :: DGNodeLab -> Bool

hasOpenGoals dgn =

case dgn_theory dgn of

G_theory _lid _sigma sens ->

OMap.null $ OMap.filter

(\s -> not (Logic.Prover.isAxiom s) && not (isProvenSenStatus s) ) sens

-- | link inscriptions in development graphs

data DGLinkLab = DGLink {

dgl_morphism :: GMorphism, -- signature morphism of link

dgl_type :: DGLinkType, -- type: local, global, def, thm?

-- dgl_depends :: [Int],

dgl_origin :: DGOrigin } -- origin in input language

deriving (Show, Eq)

instance Pretty DGLinkLab where

pretty l = fsep [ pretty (dgl_morphism l)

, pretty (dgl_type l)

, pretty (dgl_origin l)]

-- | coarser equality, ignoring the proof status

eqDGLinkLab :: DGLinkLab -> DGLinkLab -> Bool

eqDGLinkLab l1 l2 =

dgl_morphism l1 == dgl_morphism l2

&& eqDGLinkType (dgl_type l1) (dgl_type l2)

&& dgl_origin l1 == dgl_origin l2

eqLEdgeDGLinkLab :: LEdge DGLinkLab -> LEdge DGLinkLab -> Bool

eqLEdgeDGLinkLab (m1,n1,l1) (m2,n2,l2) =

m1==m2 && n1==n2 && eqDGLinkLab l1 l2

roughElem :: LEdge DGLinkLab -> [LEdge DGLinkLab] -> Bool

roughElem x = any (`eqLEdgeDGLinkLab` x)

data DGChange = InsertNode (LNode DGNodeLab)

| DeleteNode (LNode DGNodeLab)

| InsertEdge (LEdge DGLinkLab)

| DeleteEdge (LEdge DGLinkLab)

deriving Eq

instance Show DGChange where

show (InsertNode (n, _)) = "InsertNode "++show n -- ++show l

show (DeleteNode (n, _)) = "DeleteNode "++show n -- ++show l

show (InsertEdge (n,m, _)) = "InsertEdge "++show n++"->"++show m -- ++show l

show (DeleteEdge (n,m, _)) = "DeleteEdge "++show n++"->"++show m -- ++show l

-- | Link types of development graphs

-- | Sect. IV:4.2 of the CASL Reference Manual explains them in depth

data DGLinkType = LocalDef

| GlobalDef

| HidingDef

| FreeDef MaybeNode -- the "parameter" node

| CofreeDef MaybeNode -- the "parameter" node

| LocalThm ThmLinkStatus Conservativity ThmLinkStatus

-- ??? Some more proof information is needed here

-- (proof tree, ...)

| GlobalThm ThmLinkStatus Conservativity ThmLinkStatus

| HidingThm GMorphism ThmLinkStatus

| FreeThm GMorphism Bool

-- DGLink S1 S2 m2 (DGLinkType m1 p) n

-- corresponds to a span of morphisms

-- S1 <--m1-- S --m2--> S2

deriving (Eq,Show)

thmLinkStatus :: DGLinkType -> Maybe ThmLinkStatus

thmLinkStatus (LocalThm s _ _) = Just s

thmLinkStatus (GlobalThm s _ _) = Just s

thmLinkStatus (HidingThm _ s) = Just s

thmLinkStatus _ = Nothing

-- | Coarser equality ignoring the proof status

eqDGLinkType :: DGLinkType -> DGLinkType -> Bool

LocalDef `eqDGLinkType` LocalDef = True

HidingDef `eqDGLinkType` HidingDef = True

FreeDef n1 `eqDGLinkType` FreeDef n2 = n1==n2

LocalThm _ _ _ `eqDGLinkType` LocalThm _ _ _ = True

GlobalThm _ _ _ `eqDGLinkType` GlobalThm _ _ _ = True

HidingThm m1 _ `eqDGLinkType` HidingThm m2 _ = m1 == m2

FreeThm m1 _ `eqDGLinkType` FreeThm m2 _ = m1 == m2

_ `eqDGLinkType` _ = False

instance Pretty DGLinkType where

pretty t = text $ case t of

LocalDef -> "LocalDef"

GlobalDef -> "GlobalDef"

HidingDef -> "HidingDef"

FreeDef _ -> "FreeDef"

CofreeDef _ -> "CofreeDef"

LocalThm _ _ _ -> "LocalThm"

GlobalThm _ _ _ -> "GlobalThm"

HidingThm _ _ -> "HidingThm"

FreeThm _ _ -> "FreeThm"

-- | Conservativity annotations. For compactness, only the greatest

-- | applicable value is used in a DG

data Conservativity = None | Cons | Mono | Def

deriving (Eq,Ord)

instance Show Conservativity where

show None = ""

show Cons = "Cons"

show Mono = "Mono"

show Def = "Def"

-- | Rules in the development graph calculus

-- | Sect. IV:4.4 of the CASL Reference Manual explains them in depth

data DGRule =

TheoremHideShift

| HideTheoremShift (LEdge DGLinkLab)

| Borrowing

| ConsShift

| DefShift

| MonoShift

| DefToMono

| MonoToCons

| FreeIsMono

| MonoIsFree

| GlobDecomp (LEdge DGLinkLab) -- edge in the conclusion

| LocDecomp (LEdge DGLinkLab)

| LocInference (LEdge DGLinkLab)

| GlobSubsumption (LEdge DGLinkLab)

| Composition [LEdge DGLinkLab]

| LocalInference

| BasicInference AnyComorphism BasicProof -- coding and proof tree. obsolete ?!?

| BasicConsInference Edge BasicConsProof

deriving (Show, Eq)

instance Pretty DGRule where

pretty r = case r of

TheoremHideShift -> text "Theorem-Hide-Shift"

HideTheoremShift l -> text "Hide-Theorem-Shift; resulting link:"

<+> printLEdgeInProof l

Borrowing -> text "Borrowing"

ConsShift -> text "Cons-Shift"

DefShift -> text "Def-Shift"

MonoShift -> text "Mono-Shift"

DefToMono -> text "DefToMono"

MonoToCons -> text "MonoToCons"

FreeIsMono -> text "FreeIsMono"

MonoIsFree -> text "MonoIsFree"

GlobDecomp l -> text "Global Decomposition; resulting link:"

<+> printLEdgeInProof l

LocDecomp l -> text "Local Decomposition; resulting link:"

<+> printLEdgeInProof l

LocInference l -> text "Local Inference; resulting link:"

<+> printLEdgeInProof l

GlobSubsumption l -> text "Global Subsumption; resulting link:"

<+> printLEdgeInProof l

Composition ls ->

text "Composition" <+> vcat (map printLEdgeInProof ls)

LocalInference -> text "Local Inference"

BasicInference c bp -> text "Basic Inference using:"

<+> text ("Comorphism: "++show c ++ "Proof tree: "++show bp)

BasicConsInference _ bp -> text "Basic Cons-Inference using:"

<+> text (show bp)

printLEdgeInProof :: LEdge DGLinkLab -> Doc

printLEdgeInProof (s,t,l) =

pretty s <> text "-->" <> pretty t <> text ":"

<+> printLabInProof l

printLabInProof :: DGLinkLab -> Doc

printLabInProof l =

fsep [ pretty (dgl_type l)

, text "with origin:"

, pretty (dgl_origin l) <> comma

, text "and morphism:"

, pretty (dgl_morphism l)

]

data BasicProof =

forall lid sublogics

basic_spec sentence symb_items symb_map_items

sign morphism symbol raw_symbol proof_tree .

Logic lid sublogics

basic_spec sentence symb_items symb_map_items

sign morphism symbol raw_symbol proof_tree =>

BasicProof lid (Proof_status proof_tree)

| Guessed

| Conjectured

| Handwritten

instance Eq BasicProof where

Guessed == Guessed = True

Conjectured == Conjectured = True

Handwritten == Handwritten = True

BasicProof lid1 p1 == BasicProof lid2 p2 =

coerceBasicProof lid1 lid2 "Eq BasicProof" p1 == Just p2

_ == _ = False

instance Ord BasicProof where

Guessed <= _ = True

Conjectured <= x = case x of

Guessed -> False

_ -> True

Handwritten <= x = case x of

Guessed -> False

Conjectured -> False

_ -> True

BasicProof lid1 pst1 <= x =

case x of

BasicProof lid2 pst2

| isProvedStat pst1 && not (isProvedStat pst2) -> False

| not (isProvedStat pst1) && isProvedStat pst2 -> True

| otherwise -> case primCoerce lid1 lid2 "" pst1 of

Nothing -> False

Just pst1' -> pst1' <= pst2

_ -> False

instance Show BasicProof where

show (BasicProof _ p1) = show p1

show Guessed = "Guessed"

show Conjectured = "Conjectured"

show Handwritten = "Handwritten"

basicProofTc :: TyCon

basicProofTc = mkTyCon "Static.DevGraph.BasicProof"

instance Typeable BasicProof where

typeOf _ = mkTyConApp basicProofTc []

data BasicConsProof = BasicConsProof -- more detail to be added ...

deriving (Show, Eq)

data ThmLinkStatus = LeftOpen

| Proven DGRule [LEdge DGLinkLab] -- Proven DGRule Int

deriving (Show, Eq)

instance Pretty ThmLinkStatus where

pretty tls = case tls of

LeftOpen -> text "Open"

Proven r ls -> fsep [ text "Proven with rule"

, pretty r

, text "Proof based on links:"

] $+$ vcat(map printLEdgeInProof ls)

-- | Data type indicating the origin of nodes and edges in the input language

-- | This is not used in the DG calculus, only may be used in the future

-- | for reconstruction of input and management of change.

data DGOrigin = DGBasic | DGExtension | DGTranslation | DGUnion | DGHiding

| DGRevealing | DGRevealTranslation | DGFree | DGCofree

| DGLocal | DGClosed | DGClosedLenv | DGLogicQual

| DGLogicQualLenv | DGData

| DGFormalParams | DGImports | DGSpecInst SIMPLE_ID | DGFitSpec

| DGView SIMPLE_ID | DGFitView SIMPLE_ID | DGFitViewImp SIMPLE_ID

| DGFitViewA SIMPLE_ID | DGFitViewAImp SIMPLE_ID | DGProof

| DGintegratedSCC

deriving (Show, Eq)

type DGraph = Tree.Gr DGNodeLab DGLinkLab

{- type DGraph = DGraph { dgraph :: Tree.Gr DGNodeLab Int

, dgptr :: Int

, dglabels :: Map.Map Int (LEdge DGLinkLab) }

-}

-- | Node with signature in a DG

data NodeSig = NodeSig Node G_sign deriving (Show, Eq)

-- | NodeSig or possibly the empty sig in a logic

-- | (but since we want to avoid lots of vacuous nodes with empty sig,

-- | we do not assign a real node in the DG here)

data MaybeNode = JustNode NodeSig | EmptyNode AnyLogic deriving (Show, Eq)

instance Pretty NodeSig where

pretty (NodeSig n sig) =

text "node" <+> pretty n <> colon <> pretty sig

emptyG_sign :: AnyLogic -> G_sign

emptyG_sign (Logic lid) = G_sign lid (empty_signature lid)

getSig :: NodeSig -> G_sign

getSig (NodeSig _ sigma) = sigma

getNode :: NodeSig -> Node

getNode (NodeSig n _) = n

getMaybeSig :: MaybeNode -> G_sign

getMaybeSig (JustNode ns) = getSig ns

getMaybeSig (EmptyNode l) = emptyG_sign l

getLogic :: MaybeNode -> AnyLogic

getLogic (JustNode ns) = getNodeLogic ns

getLogic (EmptyNode l) = l

getNodeLogic :: NodeSig -> AnyLogic

getNodeLogic (NodeSig _ (G_sign lid _)) = Logic lid

-- | Create a node that represents a union of signatures

nodeSigUnion :: LogicGraph -> DGraph -> [MaybeNode] -> DGOrigin

-> Result (NodeSig, DGraph)

nodeSigUnion lgraph dg nodeSigs orig =

do sigUnion@(G_sign lid sigU) <- gsigManyUnion lgraph

$ map getMaybeSig nodeSigs

let nodeContents = DGNode {dgn_name = emptyNodeName,

dgn_theory = G_theory lid sigU noSens,

dgn_nf = Nothing,

dgn_sigma = Nothing,

dgn_origin = orig,

dgn_cons = None,

dgn_cons_status = LeftOpen}

node = getNewNode dg

dg' = insNode (node, nodeContents) dg

inslink dgres nsig = do

dgv <- dgres

case nsig of

EmptyNode _ -> dgres

JustNode (NodeSig n sig) -> do

incl <- ginclusion lgraph sig sigUnion

return $ insEdge (n, node, DGLink

{dgl_morphism = incl,

dgl_type = GlobalDef,

dgl_origin = orig }) dgv

dg'' <- foldl inslink (return dg') nodeSigs

return (NodeSig node sigUnion, dg'')

-- | Extend the development graph with given morphism originating

-- from given NodeSig

extendDGraph :: DGraph -- ^ the development graph to be extended

-> NodeSig -- ^ the NodeSig from which the morphism originates

-> GMorphism -- ^ the morphism to be inserted

-> DGOrigin

-> Result (NodeSig, DGraph)

-- ^ returns the target signature of the morphism and the resulting DGraph

extendDGraph dg (NodeSig n _) morph orig = case cod Grothendieck morph of

targetSig@(G_sign lid tar) -> let

nodeContents = DGNode {dgn_name = emptyNodeName,

dgn_theory = G_theory lid tar noSens,

dgn_nf = Nothing,

dgn_sigma = Nothing,

dgn_origin = orig,

dgn_cons = None,

dgn_cons_status = LeftOpen}

linkContents = DGLink {dgl_morphism = morph,

dgl_type = GlobalDef, -- TODO: other type

dgl_origin = orig}

node = getNewNode dg

dg' = insNode (node, nodeContents) dg

dg'' = insEdge (n, node, linkContents) dg'

in return (NodeSig node targetSig, dg'')

-- | Extend the development graph with given morphism pointing to

-- given NodeSig

extendDGraphRev :: DGraph -- ^ the development graph to be extended

-> NodeSig -- ^ the NodeSig to which the morphism points

-> GMorphism -- ^ the morphism to be inserted

-> DGOrigin

-> Result (NodeSig, DGraph)

-- ^ returns the source signature of the morphism and the resulting DGraph

extendDGraphRev dg (NodeSig n _) morph orig = case dom Grothendieck morph of

sourceSig@(G_sign lid src) -> let

nodeContents = DGNode {dgn_name = emptyNodeName,

dgn_theory = G_theory lid src OMap.empty,

dgn_nf = Nothing,

dgn_sigma = Nothing,

dgn_origin = orig,

dgn_cons = None,

dgn_cons_status = LeftOpen}

linkContents = DGLink {dgl_morphism = morph,

dgl_type = GlobalDef, -- TODO: other type

dgl_origin = orig}

node = getNewNode dg

dg' = insNode (node, nodeContents) dg

dg'' = insEdge (node, n, linkContents) dg'

in return (NodeSig node sourceSig, dg'')

-- import, formal parameters and united signature of formal params

type GenericitySig = (MaybeNode, [NodeSig], MaybeNode)

-- import, formal parameters, united signature of formal params, body

type ExtGenSig = (MaybeNode, [NodeSig], G_sign, NodeSig)

-- source, morphism, parameterized target

type ExtViewSig = (NodeSig,GMorphism,ExtGenSig)

-- * Types for architectural and unit specification analysis

-- (as defined for basic static semantics in Chap. III:5.1)

data UnitSig = Unit_sig NodeSig

| Par_unit_sig [NodeSig] NodeSig

deriving Show

data ImpUnitSigOrSig = Imp_unit_sig MaybeNode UnitSig

| Sig NodeSig

deriving Show

type StUnitCtx = Map.Map SIMPLE_ID ImpUnitSigOrSig

emptyStUnitCtx :: StUnitCtx

emptyStUnitCtx = Map.empty

data ArchSig = ArchSig StUnitCtx UnitSig deriving Show

-- * Types for global and library environments

data GlobalEntry = SpecEntry ExtGenSig

| ViewEntry ExtViewSig

| ArchEntry ArchSig

| UnitEntry UnitSig

| RefEntry

deriving Show

type GlobalEnv = Map.Map SIMPLE_ID GlobalEntry

emptyHistory :: ([DGRule], [DGChange])

emptyHistory = ([], [])

type ProofHistory = [([DGRule], [DGChange])]

data GlobalContext = GlobalContext

{ globalAnnos :: GlobalAnnos

, globalEnv :: GlobalEnv

, devGraph :: DGraph

, proofHistory :: ProofHistory

} deriving Show

emptyGlobalContext :: GlobalContext

emptyGlobalContext = GlobalContext

{ globalAnnos = emptyGlobalAnnos

, globalEnv = Map.empty

, devGraph = Graph.empty

, proofHistory = [emptyHistory]

}

type LibEnv = Map.Map LIB_NAME GlobalContext

-- | an empty environment

emptyLibEnv :: LibEnv

emptyLibEnv = Map.empty

-- | returns the global context that belongs to the given library name

lookupGlobalContext :: LIB_NAME -> LibEnv -> GlobalContext

lookupGlobalContext ln =

Map.findWithDefault (error "lookupGlobalContext") ln

-- | returns the development graph that belongs to the given library name

lookupDGraph :: LIB_NAME -> LibEnv -> DGraph

lookupDGraph ln = devGraph . lookupGlobalContext ln

instance Pretty DGOrigin where

pretty origin = text $ case origin of

DGBasic -> "basic specification"

DGExtension -> "extension"

DGTranslation -> "translation"

DGUnion -> "union"

DGHiding -> "hiding"

DGRevealing -> "revealing"

DGRevealTranslation -> "translation part of a revealing"

DGFree -> "free specification"

DGCofree -> "cofree specification"

DGLocal -> "local specification"

DGClosed -> "closed specification"

DGClosedLenv -> "closed specification (inclusion of local environment)"

DGFormalParams -> "formal parameters of a generic specification"

DGImports -> "imports of a generic specification"

DGSpecInst n -> "instantiation of " ++ tokStr n

DGFitSpec -> "fittig specification"

DGView n -> "view " ++ tokStr n

DGFitView n -> "fitting view " ++ tokStr n

DGFitViewImp n -> "fitting view (imports) " ++ tokStr n

DGFitViewA n -> "fitting view (actual parameters) "++ tokStr n

DGFitViewAImp n -> "fitting view (imports and actual parameters) "

++ tokStr n

DGProof -> "constructed within a proof"

_ -> show origin

-- * Heterogenous sentences

type HetSenStatus a = SenStatus a (AnyComorphism,BasicProof)

isProvenSenStatus :: HetSenStatus a -> Bool

isProvenSenStatus = any isProvenSenStatusAux . thmStatus

where isProvenSenStatusAux (_,BasicProof _ pst) = isProvedStat pst

isProvenSenStatusAux _ = False

-- * Grothendieck theories

-- | Grothendieck theories

data G_theory = forall lid sublogics

basic_spec sentence symb_items symb_map_items

sign morphism symbol raw_symbol proof_tree .

Logic lid sublogics

basic_spec sentence symb_items symb_map_items

sign morphism symbol raw_symbol proof_tree =>

G_theory lid sign (ThSens sentence (AnyComorphism, BasicProof))

coerceThSens ::

(Logic lid1 sublogics1 basic_spec1 sentence1 symb_items1 symb_map_items1

sign1 morphism1 symbol1 raw_symbol1 proof_tree1,

Logic lid2 sublogics2 basic_spec2 sentence2 symb_items2 symb_map_items2

sign2 morphism2 symbol2 raw_symbol2 proof_tree2,

Monad m,

Typeable b) => lid1 -> lid2 -> String

-> ThSens sentence1 b -> m (ThSens sentence2 b)

coerceThSens l1 l2 msg t1 = primCoerce l1 l2 msg t1

instance Eq G_theory where

G_theory l1 sig1 sens1 == G_theory l2 sig2 sens2 =

coerceSign l1 l2 "" sig1 == Just sig2

&& coerceThSens l1 l2 "" sens1 == Just sens2

instance Show G_theory where

show (G_theory _ sign sens) =

show sign ++ "\n" ++ show sens

instance Pretty G_theory where

pretty g = case simplifyTh g of

G_theory lid sign sens ->

pretty sign $++$ vsep (map (print_named lid)

$ toNamedList sens)

-- | compute sublogic of a theory

sublogicOfTh :: G_theory -> G_sublogics

sublogicOfTh (G_theory lid sigma sens) =

let sub = foldl join

(minSublogic sigma)

(map snd $ OMap.toList $

OMap.map (minSublogic . value)

sens)

in G_sublogics lid sub

-- | simplify a theory (throw away qualifications)

simplifyTh :: G_theory -> G_theory

simplifyTh (G_theory lid sigma sens) = G_theory lid sigma $

OMap.map (mapValue $ simplify_sen lid sigma) sens

-- | apply a comorphism to a theory

mapG_theory :: AnyComorphism -> G_theory -> Result G_theory

mapG_theory (Comorphism cid) (G_theory lid sign sens) = do

bTh <- coerceBasicTheory lid (sourceLogic cid)

"mapG_theory" (sign, toNamedList sens)

(sign', sens') <- wrapMapTheory cid bTh

return $ G_theory (targetLogic cid) sign' $ toThSens sens'

-- | Translation of a G_theory along a GMorphism

translateG_theory :: GMorphism -> G_theory -> Result G_theory

translateG_theory (GMorphism cid _ morphism2) (G_theory lid sign sens) = do

let tlid = targetLogic cid

bTh <- coerceBasicTheory lid (sourceLogic cid)

"translateG_theory" (sign, toNamedList sens)

(_, sens'') <- map_theory cid bTh

sens''' <- mapM (mapNamedM $ map_sen tlid morphism2) sens''

return $ G_theory tlid (cod tlid morphism2) $ toThSens sens'''

-- | Join the sentences of two G_theories

joinG_sentences :: Monad m => G_theory -> G_theory -> m G_theory

joinG_sentences (G_theory lid1 sig1 sens1) (G_theory lid2 sig2 sens2) = do

sens2' <- coerceThSens lid2 lid1 "joinG_sentences" sens2

sig2' <- coerceSign lid2 lid1 "joinG_sentences" sig2

return $ assert (sig1 == sig2') $ G_theory lid1 sig1 $ joinSens sens1 sens2'

-- | flattening the sentences form a list of G_theories

flatG_sentences :: Monad m => G_theory -> [G_theory] -> m G_theory

flatG_sentences th ths = foldM joinG_sentences th ths

-- | Get signature of a theory

signOf :: G_theory -> G_sign

signOf (G_theory lid sign _) = G_sign lid sign

------------------------------------------------------------------

-- Grothendieck diagrams and weakly amalgamable cocones

------------------------------------------------------------------

type GDiagram = Tree.Gr G_theory GMorphism

gWeaklyAmalgamableCocone :: GDiagram

-> Result (G_theory, Map.Map Graph.Node GMorphism)

gWeaklyAmalgamableCocone _ =

return (undefined, Map.empty) -- dummy implementation