From 09f6dfa65b66103c27dc831271d961de9ab0109e Mon Sep 17 00:00:00 2001
From: Michael Andreen <harv@ruin.nu>
Date: Sat, 7 May 2005 11:03:42 +0000
Subject: [PATCH] only execute an action when all preconditions are are true

---
 node.cpp    | 11 +++++++++--
 node.h      |  3 ++-
 planner.cpp |  2 +-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/node.cpp b/node.cpp
index ed72a7f..dbb099c 100644
--- a/node.cpp
+++ b/node.cpp
@@ -1,8 +1,10 @@
 #include "node.h"
+#include <algorithm>
 using namespace std;
 
 Node::Node(Action action){
 	_action = action;
+	_preconditions = _action.preconditions();
 }
 
 Action Node::action(){
@@ -15,10 +17,15 @@ void Node::addChild(Node* node){
 }
 
 
-void Node::execute(){
+void Node::execute(literals effects){
+	for (literals::iterator effect = effects.begin(); effect != effects.end(); ++effect){
+		_preconditions.erase(find(_preconditions.begin(),_preconditions.end(), *effect));
+	}
+	if (_preconditions.size() != 0)
+		return;
 	_action.execute();
 	
 	for(vector<Node*>::iterator child = _children.begin(); child != _children.end(); ++child){
-		(*child)->execute();
+		(*child)->execute(_action.effects());
 	}
 }
diff --git a/node.h b/node.h
index 3cd3a9e..0d9cae6 100644
--- a/node.h
+++ b/node.h
@@ -10,11 +10,12 @@ class Node {
 		Node(Action action);
 		void addChild(Node* node);
 		Action action();
-		void execute();
+		void execute(literals effects);
 
 	protected:
 		Action _action;
 		std::vector<Node*> _children;
+		literals _preconditions;
 };
 
 #endif
diff --git a/planner.cpp b/planner.cpp
index 4630494..a15028e 100644
--- a/planner.cpp
+++ b/planner.cpp
@@ -61,5 +61,5 @@ void Planner::addNode(Node* node){
 
 
 void Planner::execute(){
-	_start->execute();
+	_start->execute(literals());
 }
-- 
2.39.2