improve backtracking

tuProlog · Jun 18, 2020 · 121aecc · 121aecc
1 parent 2301547
commit 121aecc
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Showing 2 changed files with 22 additions and 8 deletions.
diff --git a/solve-classic/src/commonMain/kotlin/it/unibo/tuprolog/solve/ChoicePointContext.kt b/solve-classic/src/commonMain/kotlin/it/unibo/tuprolog/solve/ChoicePointContext.kt
@@ -56,7 +56,7 @@ sealed class ChoicePointContext(
 
     protected abstract val typeName: String
 
-    abstract fun backtrack(nextStep: Long, startTime: Long): ClassicExecutionContext
+    abstract fun backtrack(context: ClassicExecutionContext): ClassicExecutionContext
 
     data class Primitives(
         override val alternatives: Cursor<out Solve.Response>,
@@ -72,11 +72,18 @@ sealed class ChoicePointContext(
         override val typeName: String
             get() = "Primitives"
 
-        override fun backtrack(nextStep: Long, startTime: Long): ClassicExecutionContext {
+        override fun backtrack(context: ClassicExecutionContext): ClassicExecutionContext {
             val tempContext = executionContext!!.copy(
                 primitives = alternatives,
-                step = nextStep,
-                startTime = startTime
+                step = context.step + 1,
+                startTime = context.startTime,
+                flags = context.flags,
+                dynamicKb = context.dynamicKb,
+                staticKb = context.staticKb,
+                operators = context.operators,
+                inputChannels = context.inputChannels,
+                outputChannels = context.outputChannels,
+                libraries = context.libraries
             )
 
             val nextChoicePointContext = copy(
@@ -102,11 +109,18 @@ sealed class ChoicePointContext(
         override val typeName: String
             get() = "Rules"
 
-        override fun backtrack(nextStep: Long, startTime: Long): ClassicExecutionContext {
+        override fun backtrack(context: ClassicExecutionContext): ClassicExecutionContext {
             val tempContext = executionContext!!.copy(
                 rules = alternatives,
-                step = nextStep,
-                startTime = startTime
+                step = context.step + 1,
+                startTime = context.startTime,
+                flags = context.flags,
+                dynamicKb = context.dynamicKb,
+                staticKb = context.staticKb,
+                operators = context.operators,
+                inputChannels = context.inputChannels,
+                outputChannels = context.outputChannels,
+                libraries = context.libraries
             )
 
             val nextChoicePointContext = copy(

diff --git a/solve-classic/src/commonMain/kotlin/it/unibo/tuprolog/solve/fsm/StateBacktracking.kt b/solve-classic/src/commonMain/kotlin/it/unibo/tuprolog/solve/fsm/StateBacktracking.kt
@@ -13,7 +13,7 @@ internal data class StateBacktracking(override val context: ClassicExecutionCont
             )
         } else {
             val choicePointContext = choicePoints!!.pathToRoot.first { it.alternatives.hasNext }
-            val nextContext = choicePointContext.backtrack(nextStep(), context.startTime)
+            val nextContext = choicePointContext.backtrack(context)
             if (nextContext.primitives.hasNext) {
                 StatePrimitiveExecution(nextContext)
             } else {