From 1513ea3ac714b9d0f23aa12563d6643359af81b7 Mon Sep 17 00:00:00 2001
From: Sverre Rabbelier <alturin@gmail.com>
Date: Mon, 14 Apr 2008 12:07:04 +0200
Subject: [PATCH] Only allow this language: ((n|s)!(w|e)!(u|d)!;)+ for
 directions.

Example:
good: nwu
bad: wus
bad: wws
bad: nsu
---
 src/Core/Editors/DirectionParser.cpp | 64 ++++++++++++++++++++----------------
 1 file changed, 35 insertions(+), 29 deletions(-)

diff --git a/src/Core/Editors/DirectionParser.cpp b/src/Core/Editors/DirectionParser.cpp
index d14eea5..eb5f162 100644
--- a/src/Core/Editors/DirectionParser.cpp
+++ b/src/Core/Editors/DirectionParser.cpp
@@ -26,27 +26,21 @@
 
 using namespace boost::spirit;
 
-struct dirs : symbols<Coordinate>
-{
-    dirs()
-    {
-        add
-            ("n",	Coordinate(1,	0,	0))
-            ("s",	Coordinate(-1,	0,	0))
-            ("e",	Coordinate(0,	1,	0))
-            ("w",	Coordinate(0,	-1,	0))
-			("u",	Coordinate(0,	0,	1))
-			("d",	Coordinate(0,	0,	-1))
-        ;
-    }
-
-} dirs_p;
-
 struct add_dir
 {
-    add_dir(Coordinate& coordinate) : m_coordinate(coordinate) {}
-    void operator()(Coordinate& rhs) const { m_coordinate += rhs; }
+    add_dir(Coordinate& coordinate, Coordinate rhs) : 
+	m_coordinate(coordinate), 
+	m_rhs(rhs) 
+	{
+
+	}
+	
+    void operator()(const char&) const 
+	{ 
+		m_coordinate += m_rhs; 
+	}
     Coordinate& m_coordinate;
+	Coordinate m_rhs;
 };
 
 struct add_and_reset
@@ -55,12 +49,13 @@ struct add_and_reset
 	m_coordinates(coordinates), 
 	m_coordinate(coordinate) 
 	{ 
-		
+
 	}
 	
     void operator()(char const*, char const*) const {
-		m_coordinates.push_back(m_coordinate);
-		m_coordinate = m_coordinate - m_coordinate;
+		Coordinate copy = m_coordinate;
+		m_coordinates.push_back(copy);
+		m_coordinate = m_coordinate - copy;
 	}
 	
 	std::vector<Coordinate>& m_coordinates;
@@ -74,18 +69,29 @@ struct direction : public grammar<direction>
     struct definition
     {
         definition(direction const& self)
-        {			
+        {
 			// Create the rule that will match a directional component
-			
 			first = 
 				list_p(
-						// Allow arbitrary many direction components
-						(dirs_p[ add_dir(self.m_coordinate) ]) >>
-						!(dirs_p[ add_dir(self.m_coordinate) ]) >>
-						!(dirs_p[ add_dir(self.m_coordinate) ]) >>
-						eps_p[add_and_reset(self.m_coordinates, self.m_coordinate)],
+							!(
+								ch_p('n')[add_dir(self.m_coordinate, Coordinate(1,	0, 0))] |
+								ch_p('s')[add_dir(self.m_coordinate, Coordinate(-1,	0, 0))]
+							) >>
+							
+							!(
+								ch_p('w')[add_dir(self.m_coordinate, Coordinate(0, 1,	0))] |
+								ch_p('e')[add_dir(self.m_coordinate, Coordinate(0, -1,	0))]
+							) >>
+							
+							!(
+								ch_p('u')[add_dir(self.m_coordinate, Coordinate(0, 0, 1	))] |
+								ch_p('d')[add_dir(self.m_coordinate, Coordinate(0, 0, -1))]
+							) >>
+									
+							eps_p[add_and_reset(self.m_coordinates, self.m_coordinate)],
+							
 						ch_p(';')
-					);					
+					);
         }
 
         rule<ScannerT> first;
-- 
2.11.4.GIT