{- |
Module :
Copyright : (c) Cui Jian, Till Mossakowski, Uni Bremen 2002-2006
Description : simple version of theorem hide shift proof rule
License : GPLv2 or higher, see LICENSE.txt
Maintainer : Christian.Maeder@dfki.de
Stability : provisional
Portability : non-portable(Logic)
simple version of theorem hide shift proof rule for development graphs.
Follows Sect. IV:4.4 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.
it relates to the ticket 13
-}
( theoremHideShift
, thmHideShift
, getInComingGlobalUnprovenEdges
) where
import Proofs.EdgeUtils
import Static.DevGraph
import Static.DgUtils
import Static.History
import Common.LibName
import qualified Data.Map as Map
import Data.Graph.Inductive.Graph
import Data.Maybe (fromMaybe)
-- | rule name
thmHideShift :: DGRule
thmHideShift = DGRule "TheoremHideShift"
{- | to be exported function.
firstly it gets all the hiding definition links out of DGraph and
passes them to theoremHideShiftFromList which does the actual processing
-}
theoremHideShift :: LibName -> LibEnv -> LibEnv
theoremHideShift ln proofStatus =
let dgraph = lookupDGraph ln proofStatus
hidingDefEdges = filter (liftE isHidingDef) $ labEdgesDG dgraph
newDGraph = foldl theoremHideShiftFromList dgraph hidingDefEdges
in Map.insert ln newDGraph proofStatus
{- | apply the theorem hide shift with a list of hiding definition links.
it calls the function for one hiding edge at a time and fills the history
if necessary.
-}
theoremHideShiftFromList :: DGraph -> LEdge DGLinkLab -> DGraph
theoremHideShiftFromList dgraph e = let
newDGraph = theoremHideShiftWithOneHidingDefEdge dgraph e
in groupHistory dgraph thmHideShift newDGraph
{- | apply the rule to one hiding definition link.
it takes all the related global unproven edges to the given hiding edge
and passes them together to its auxiliary function.
-}
theoremHideShiftWithOneHidingDefEdge :: DGraph -> LEdge DGLinkLab -> DGraph
theoremHideShiftWithOneHidingDefEdge dgraph e@(_, n, _) =
foldl (theoremHideShiftWithOneHidingDefEdgeAux e) dgraph
$ getInComingGlobalUnprovenEdges dgraph n
{- | get all the global unproven threorem links which go into the given
node in the given dgraph
-}
getInComingGlobalUnprovenEdges :: DGraph -> Node -> [LEdge DGLinkLab]
getInComingGlobalUnprovenEdges dgraph =
filter (liftE isUnprovenGlobalThm) . innDG dgraph
{- | it's the main function of this simplified theorem hide shift.
it applies the rule to a list of global unproven threorem links
with the related hiding definition link. It contains three steps
fulfilling the task and is marked below.
-}
theoremHideShiftWithOneHidingDefEdgeAux :: LEdge DGLinkLab -> DGraph
-> LEdge DGLinkLab -> DGraph
theoremHideShiftWithOneHidingDefEdgeAux hd@(hds, _, _) dgraph x@(s, t, lbl) =
let
newMorphism = fromMaybe (error
calculateMorphismOfPath [x, hd]
newGlobalEdge = (s, hds, defDGLink newMorphism globalThm DGLinkProof)
(newDGraph, proofbasis) =
tryToInsertEdgeAndSelectProofBasis dgraph newGlobalEdge emptyProofBasis
-- ------ to insert a proven global theorem link ---------------
provenEdge = (s, t, lbl
{ dgl_type = setProof (Proven thmHideShift
proofbasis) $ dgl_type lbl
, dgl_origin = DGLinkProof })
in changesDGH newDGraph [DeleteEdge x, InsertEdge provenEdge]
{- | it tries to insert the given edge into the DGraph and selects the
inserted edge as proof basis if possible.
-}
tryToInsertEdgeAndSelectProofBasis :: DGraph -> LEdge DGLinkLab -> ProofBasis
-> (DGraph, ProofBasis)
tryToInsertEdgeAndSelectProofBasis dgraph newEdge proofbasis =
case tryToGetEdge newEdge dgraph of
Just tempE -> (dgraph, addEdgeId proofbasis $ getEdgeId tempE)
Nothing -> let
tempDGraph = changeDGH dgraph $ InsertEdge newEdge
tempPB = case getLastChange tempDGraph of
InsertEdge tempE -> addEdgeId proofbasis $ getEdgeId tempE
_ -> error
in (tempDGraph, tempPB)