"Committed_by_peb"

src/GF/Data/IncrementalDeduction.hs

@@ -0,0 +1,64 @@
+----------------------------------------------------------------------
+-- |
+-- Maintainer  : PL
+-- Stability   : (stable)
+-- Portability : (portable)
+--
+-- > CVS $Date: 2005/04/11 13:52:51 $ 
+-- > CVS $Author: peb $
+-- > CVS $Revision: 1.1 $
+--
+-- Implementation of /incremental/ deductive parsing,
+-- i.e. parsing one word at the time.
+-----------------------------------------------------------------------------
+
+module GF.NewParsing.IncrementalChart
+    (-- * Type definitions
+     IncrementalChart,
+     -- * Functions
+     chartLookup,
+     buildChart,
+     chartList
+    ) where
+
+import Array
+import GF.Data.SortedList
+import GF.Data.Assoc
+
+----------------------------------------------------------------------
+-- main functions 
+
+chartLookup :: (Ord item, Ord key) =>
+	       IncrementalChart item key
+	    -> Int -> key -> SList item
+
+buildChart :: (Ord item, Ord key) => 
+	      (item -> key)               -- ^ key lookup function
+	   -> (Int -> item -> SList item) -- ^ all inference rules for position k, collected
+	   -> (Int ->         SList item) -- ^ all axioms for position k, collected
+	   -> (Int, Int)                  -- ^ input bounds
+	   -> IncrementalChart item key
+
+chartList :: (Ord item, Ord key) => 
+	     IncrementalChart item key    -- ^ the final chart
+	  -> (Int -> item -> edge)        -- ^ function building an edge from 
+					  -- the position and the item
+	  -> [edge]
+
+type IncrementalChart item key = Array Int (Assoc key (SList item))
+
+----------
+
+chartLookup chart k key = (chart ! k) ? key
+
+buildChart keyof rules axioms bounds = finalChartArray
+    where buildState k     = limit (rules k) $ axioms k
+	  finalChartList   = map buildState [fst bounds .. snd bounds]
+	  finalChartArray  = listArray bounds $ map stateAssoc finalChartList
+	  stateAssoc state = accumAssoc id [ (keyof item, item) | item <- state ]
+
+chartList chart combine = [ combine k item | 
+			    (k, state) <- assocs chart, 
+			    item <- concatMap snd $ aAssocs state ]
+
+