Getting ready to improve native function resolution and definition.

context.hpp

 #define SASS_CONTEXT
 
-#ifndef SASS_ENVIRONMENT
+//#ifndef SASS_ENVIRONMENT
 #include "environment.hpp"
-#endif
+//#endif
 
 #include <utility>
+
+#ifndef SASS_NODE_FACTORY
 #include "node_factory.hpp"
+#endif
+
+#ifndef SASS_FUNCTIONS
 #include "functions.hpp"
+#endif
 
 namespace Sass {
   using std::pair;
   using std::map;
   
-  // struct Environment {
-  //   map<Token, Node> current_frame;
-  //   Environment* parent;
-  //   Environment* global;
-    
-  //   Environment()
-  //   : current_frame(map<Token, Node>()), parent(0), global(0)
-  //   { }
-    
-  //   void link(Environment& env)
-  //   {
-  //     parent = &env;
-  //     global = parent->global ? parent->global : parent;
-  //   }
-    
-  //   bool query(const Token& key) const
-  //   {
-  //     if (current_frame.count(key)) return true;
-  //     else if (parent)              return parent->query(key);
-  //     else                          return false;
-  //   }
-    
-  //   Node& operator[](const Token& key)
-  //   {
-  //     if (current_frame.count(key)) return current_frame[key];
-  //     else if (parent)              return (*parent)[key];
-  //     else                          return current_frame[key];
-  //   }
-  // };
-
   struct Context {
     Environment global_env;
     map<string, Function> function_env;

document.hpp

+#define SASS_DOCUMENT
+
 #include <map>
 
 #ifndef SASS_PRELEXER

error.hpp

+#define SASS_ERROR
+
 namespace Sass {
   
   struct Error {

eval_apply.hpp

+#define SASS_EVAL_APPLY
+
 #include <map>
 
 #ifndef SASS_NODE

functions.cpp

 #ifndef SASS_PRELEXER
 #include "prelexer.hpp"
 #endif
+
 #include "node_factory.hpp"
 #include "functions.hpp"
+#include "context.hpp"
 #include "error.hpp"
+
 #include <iostream>
 #include <cmath>
+
 using std::cerr; using std::endl;
 
 namespace Sass {
+
+  Function::Function(const char* signature, Primitive ip, Node_Factory& new_Node)
+  {
+    //Document sig_doc(Document::make_from_source_chars(
+  }
+
+
   namespace Functions {
 
     static void throw_eval_error(string message, string path, size_t line)
@@ -19,6 +30,11 @@ namespace Sass {
       throw Error(Error::evaluation, path, line, message);
     }
 
+    extern const char foo_sig[] = "foo($x, $y, $z: hey hey)";
+    Node foo(const Node parameters, Environment& bindings, Node_Factory& new_Node) {
+      return Node();
+    }
+
     // RGB Functions ///////////////////////////////////////////////////////
 
     Function_Descriptor rgb_descriptor = 

functions.hpp

+#define SASS_FUNCTIONS
+
 #include <cstring>
 #include <map>
 
@@ -26,6 +28,7 @@ namespace Sass {
     Function()
     { /* TO DO: set up the generic callback here */ }
 
+    // for user-defined functions
     Function(Node def)
     : name(def[0].to_string()),
       parameters(def[1]),
@@ -42,6 +45,8 @@ namespace Sass {
       primitive(0),
       overloaded(overloaded)
     { }
+
+    Function(const char* signature, Primitive ip, Node_Factory& new_Node);
     
     Function(Function_Descriptor d, Primitive ip, Node_Factory& new_Node)
     : name(d[0]),

node_factory.hpp

+#define SASS_NODE_FACTORY
+
 #include <vector>
 
 #ifndef SASS_NODE

sass_interface.h

+#define SASS_INTERFACE
+
 #ifdef __cplusplus
 extern "C" {
 #endif