SpiderScript - Restructured to be able to keep bytecode and AST in memory at one...
[tpg/acess2.git] / Usermode / Libraries / libspiderscript.so_src / exec_ast.c
index e0de9ff..d4c7995 100644 (file)
 /*
+ * SpiderScript Library
+ *
+ * AST Execution
  */
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
 #include <string.h>
+#include "common.h"
 #include "ast.h"
 
+#define TRACE_VAR_LOOKUPS      0
+#define TRACE_NODE_RETURNS     0
+
 // === IMPORTS ===
 extern tSpiderFunction *gpExports_First;
 
 // === PROTOTYPES ===
-void   Object_Dereference(tSpiderValue *Object);
-void   Object_Reference(tSpiderValue *Object);
-tSpiderValue   *SpiderScript_CreateInteger(uint64_t Value);
-tSpiderValue   *SpiderScript_CreateReal(double Value);
-tSpiderValue   *SpiderScript_CreateString(int Length, const char *Data);
-tSpiderValue   *SpiderScript_CastValueTo(int Type, tSpiderValue *Source);
- int   SpiderScript_IsValueTrue(tSpiderValue *Value);
-void   SpiderScript_FreeValue(tSpiderValue *Value);
-char   *SpiderScript_DumpValue(tSpiderValue *Value);
-
+// - Node Execution
 tSpiderValue   *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node);
-tSpiderValue   *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpiderValue *Left, tSpiderValue *Right);
-
-tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Name);
- int   Variable_SetValue(tAST_BlockState *Block, const char *Name, tSpiderValue *Value);
-tSpiderValue   *Variable_GetValue(tAST_BlockState *Block, const char *Name);
+tSpiderValue   *AST_ExecuteNode_BinOp(tSpiderScript *Script, tAST_Node *Node, int Operation, tSpiderValue *Left, tSpiderValue *Right);
+tSpiderValue   *AST_ExecuteNode_UniOp(tSpiderScript *Script, tAST_Node *Node, int Operation, tSpiderValue *Value);
+// - Variables
+tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Name, tSpiderValue *Value);
+ int   Variable_SetValue(tAST_BlockState *Block, tAST_Node *VarNode, tSpiderValue *Value);
+tSpiderValue   *Variable_GetValue(tAST_BlockState *Block, tAST_Node *VarNode);
 void   Variable_Destroy(tAST_Variable *Variable);
-
+// - Errors
+void   AST_RuntimeMessage(tAST_Node *Node, const char *Type, const char *Format, ...);
 void   AST_RuntimeError(tAST_Node *Node, const char *Format, ...);
 
-// === CODE ===
-/**
- * \brief Dereference a created object
- */
-void Object_Dereference(tSpiderValue *Object)
-{
-       if(!Object)     return ;
-       if(Object == ERRPTR)    return ;
-       Object->ReferenceCount --;
-//     printf("%p Dereferenced (%i)\n", Object, Object->ReferenceCount);
-       if( Object->ReferenceCount == 0 ) {
-               switch( (enum eSpiderScript_DataTypes) Object->Type )
-               {
-               case SS_DATATYPE_OBJECT:
-                       Object->Object->Type->Destructor( Object->Object );
-                       break;
-               case SS_DATATYPE_OPAQUE:
-                       Object->Opaque.Destroy( Object->Opaque.Data );
-                       break;
-               default:
-                       break;
-               }
-               free(Object);
-       }
-}
-
-void Object_Reference(tSpiderValue *Object)
-{
-       if(!Object)     return ;
-       Object->ReferenceCount ++;
-//     printf("%p Referenced (%i)\n", Object, Object->ReferenceCount);
-}
-
-/**
- * \brief Allocate and initialise a SpiderScript object
- */
-tSpiderObject *SpiderScript_AllocateObject(tSpiderObjectDef *Class, int ExtraBytes)
-{
-        int    size = sizeof(tSpiderObject) + Class->NAttributes * sizeof(tSpiderValue*) + ExtraBytes;
-       tSpiderObject   *ret = malloc(size);
-       
-       ret->Type = Class;
-       ret->ReferenceCount = 1;
-       ret->OpaqueData = &ret->Attributes[ Class->NAttributes ];
-       memset( ret->Attributes, 0, Class->NAttributes * sizeof(tSpiderValue*) );
-       
-       return ret;
-}
-
-/**
- * \brief Create an integer object
- */
-tSpiderValue *SpiderScript_CreateInteger(uint64_t Value)
-{
-       tSpiderValue    *ret = malloc( sizeof(tSpiderValue) );
-       ret->Type = SS_DATATYPE_INTEGER;
-       ret->ReferenceCount = 1;
-       ret->Integer = Value;
-       return ret;
-}
+// === GLOBALS ===
+ int   giNextBlockIdent = 1;
 
-/**
- * \brief Create an real number object
- */
-tSpiderValue *SpiderScript_CreateReal(double Value)
-{
-       tSpiderValue    *ret = malloc( sizeof(tSpiderValue) );
-       ret->Type = SS_DATATYPE_REAL;
-       ret->ReferenceCount = 1;
-       ret->Real = Value;
-       return ret;
-}
-
-/**
- * \brief Create an string object
- */
-tSpiderValue *SpiderScript_CreateString(int Length, const char *Data)
-{
-       tSpiderValue    *ret = malloc( sizeof(tSpiderValue) + Length + 1 );
-       ret->Type = SS_DATATYPE_STRING;
-       ret->ReferenceCount = 1;
-       ret->String.Length = Length;
-       if( Data )
-               memcpy(ret->String.Data, Data, Length);
-       else
-               memset(ret->String.Data, 0, Length);
-       ret->String.Data[Length] = '\0';
-       return ret;
-}
-
-/**
- * \brief Concatenate two strings
- */
-tSpiderValue *Object_StringConcat(tSpiderValue *Str1, tSpiderValue *Str2)
+// === CODE ===
+tSpiderValue *AST_ExecuteFunction(tSpiderScript *Script, tScript_Function *Fcn, int NArguments, tSpiderValue **Arguments)
 {
-        int    newLen = 0;
+       tAST_BlockState bs;
        tSpiderValue    *ret;
-       if(Str1)        newLen += Str1->String.Length;
-       if(Str2)        newLen += Str2->String.Length;
-       ret = malloc( sizeof(tSpiderValue) + newLen + 1 );
-       ret->Type = SS_DATATYPE_STRING;
-       ret->ReferenceCount = 1;
-       ret->String.Length = newLen;
-       if(Str1)
-               memcpy(ret->String.Data, Str1->String.Data, Str1->String.Length);
-       if(Str2) {
-               if(Str1)
-                       memcpy(ret->String.Data+Str1->String.Length, Str2->String.Data, Str2->String.Length);
-               else
-                       memcpy(ret->String.Data, Str2->String.Data, Str2->String.Length);
-       }
-       ret->String.Data[ newLen ] = '\0';
-       return ret;
-}
-
-/**
- * \brief Cast one object to another
- * \brief Type Destination type
- * \brief Source       Input data
- */
-tSpiderValue *SpiderScript_CastValueTo(int Type, tSpiderValue *Source)
-{
-       tSpiderValue    *ret = ERRPTR;
-        int    len = 0;
-
-       if( !Source )   return NULL;
-       
-       // Check if anything needs to be done
-       if( Source->Type == Type ) {
-               Object_Reference(Source);
-               return Source;
-       }
-       
-       #if 0
-       if( Source->Type == SS_DATATYPE_OBJECT )
+        int    i = 0;
+       
+       // Build a block State
+       bs.FirstVar = NULL;
+       bs.RetVal = NULL;
+       bs.Parent = NULL;
+       bs.BaseNamespace = &Script->Variant->RootNamespace;
+       bs.CurNamespace = NULL;
+       bs.Script = Script;
+       bs.Ident = giNextBlockIdent ++;
+       
+       // Parse arguments
+       for( i = 0; i < Fcn->ArgumentCount; i ++ )
        {
-               const char      *name = NULL;
-               switch(Type)
-               {
-               case SS_DATATYPE_INTEGER:       name = "cast Integer";  break;
-               case SS_DATATYPE_REAL:          name = "cast Real";     break;
-               case SS_DATATYPE_STRING:        name = "cast String";   break;
-               case SS_DATATYPE_ARRAY:         name = "cast Array";    break;
-               default:
-                       AST_RuntimeError(NULL, "Invalid cast to %i from Object", Type);
-                       return ERRPTR;
-               }
-               if( fcnname )
-               {
-                       ret = Object_ExecuteMethod(Left->Object, fcnname, Right);
-                       if( ret != ERRPTR )
-                               return ret;
-                       // Fall through and try casting (which will usually fail)
-               }
-       }
-       #endif
-       
-       switch( (enum eSpiderScript_DataTypes)Type )
-       {
-       case SS_DATATYPE_UNDEF:
-       case SS_DATATYPE_ARRAY:
-       case SS_DATATYPE_OPAQUE:
-       case SS_DATATYPE_OBJECT:
-               AST_RuntimeError(NULL, "Invalid cast to %i", Type);
-               return ERRPTR;
-       
-       case SS_DATATYPE_INTEGER:
-               ret = malloc(sizeof(tSpiderValue));
-               ret->Type = SS_DATATYPE_INTEGER;
-               ret->ReferenceCount = 1;
-               switch(Source->Type)
-               {
-               case SS_DATATYPE_INTEGER:       break;  // Handled above
-               case SS_DATATYPE_STRING:        ret->Integer = atoi(Source->String.Data);       break;
-               case SS_DATATYPE_REAL:  ret->Integer = Source->Real;    break;
-               default:
-                       AST_RuntimeError(NULL, "Invalid cast from %i to Integer", Source->Type);
-                       free(ret);
-                       ret = ERRPTR;
-                       break;
-               }
-               break;
-       
-       case SS_DATATYPE_STRING:
-               switch(Source->Type)
-               {
-               case SS_DATATYPE_INTEGER:       len = snprintf(NULL, 0, "%li", Source->Integer);        break;
-               case SS_DATATYPE_REAL:  snprintf(NULL, 0, "%f", Source->Real);  break;
-               default:        break;
-               }
-               ret = malloc(sizeof(tSpiderValue) + len + 1);
-               ret->Type = SS_DATATYPE_STRING;
-               ret->ReferenceCount = 1;
-               ret->String.Length = len;
-               switch(Source->Type)
-               {
-               case SS_DATATYPE_INTEGER:       sprintf(ret->String.Data, "%li", Source->Integer);      break;
-               case SS_DATATYPE_REAL:  sprintf(ret->String.Data, "%f", Source->Real);  break;
-               default:
-                       AST_RuntimeError(NULL, "Invalid cast from %i to String", Source->Type);
-                       free(ret);
-                       ret = ERRPTR;
-                       break;
-               }
-               break;
-       
-       default:
-               AST_RuntimeError(NULL, "BUG - BUG REPORT: Unimplemented cast target");
-               break;
+               if( i >= NArguments )   break;  // TODO: Return gracefully
+               // TODO: Type checks
+               Variable_Define(&bs,
+                       Fcn->Arguments[i].Type, Fcn->Arguments[i].Name,
+                       Arguments[i]);
        }
-       
-       return ret;
-}
-
-/**
- * \brief Condenses a value down to a boolean
- */
-int SpiderScript_IsValueTrue(tSpiderValue *Value)
-{
-       if( Value == ERRPTR )   return 0;
-       if( Value == NULL )     return 0;
-       
-       switch( (enum eSpiderScript_DataTypes)Value->Type )
+                       
+       // Execute function
+       ret = AST_ExecuteNode(&bs, Fcn->ASTFcn);
+       if(ret != ERRPTR)
        {
-       case SS_DATATYPE_UNDEF:
-               return 0;
-       
-       case SS_DATATYPE_INTEGER:
-               return !!Value->Integer;
-       
-       case SS_DATATYPE_REAL:
-               return (-.5f < Value->Real && Value->Real < 0.5f);
-       
-       case SS_DATATYPE_STRING:
-               return Value->String.Length > 0;
-       
-       case SS_DATATYPE_OBJECT:
-               return Value->Object != NULL;
-       
-       case SS_DATATYPE_OPAQUE:
-               return Value->Opaque.Data != NULL;
-       
-       case SS_DATATYPE_ARRAY:
-               return Value->Array.Length > 0;
-       default:
-               AST_RuntimeError(NULL, "Unknown type %i in SpiderScript_IsValueTrue", Value->Type);
-               return 0;
+               SpiderScript_DereferenceValue(ret);     // Dereference output of last block statement
+               ret = bs.RetVal;        // Set to return value of block
        }
-       return 0;
-}
-
-/**
- * \brief Free a value
- * \note Just calls Object_Dereference
- */
-void SpiderScript_FreeValue(tSpiderValue *Value)
-{
-       Object_Dereference(Value);
-}
-
-/**
- * \brief Dump a value into a string
- * \return Heap string
- */
-char *SpiderScript_DumpValue(tSpiderValue *Value)
-{
-       char    *ret;
-       if( Value == ERRPTR )
-               return strdup("ERRPTR");
-       if( Value == NULL )
-               return strdup("null");
-       
-       switch( (enum eSpiderScript_DataTypes)Value->Type )
+                       
+       while(bs.FirstVar)
        {
-       case SS_DATATYPE_UNDEF: return strdup("undefined");
-       
-       case SS_DATATYPE_INTEGER:
-               ret = malloc( sizeof(Value->Integer)*2 + 3 );
-               sprintf(ret, "0x%lx", Value->Integer);
-               return ret;
-       
-       case SS_DATATYPE_REAL:
-               ret = malloc( sprintf(NULL, "%f", Value->Real) + 1 );
-               sprintf(ret, "%f", Value->Real);
-               return ret;
-       
-       case SS_DATATYPE_STRING:
-               ret = malloc( Value->String.Length + 3 );
-               ret[0] = '"';
-               strcpy(ret+1, Value->String.Data);
-               ret[Value->String.Length+1] = '"';
-               ret[Value->String.Length+2] = '\0';
-               return ret;
-       
-       case SS_DATATYPE_OBJECT:
-               ret = malloc( sprintf(NULL, "{%s *%p}", Value->Object->Type->Name, Value->Object) + 1 );
-               sprintf(ret, "{%s *%p}", Value->Object->Type->Name, Value->Object);
-               return ret;
-       
-       case SS_DATATYPE_OPAQUE:
-               ret = malloc( sprintf(NULL, "*%p", Value->Opaque.Data) + 1 );
-               sprintf(ret, "*%p", Value->Opaque.Data);
-               return ret;
-       
-       case SS_DATATYPE_ARRAY:
-               return strdup("Array");
-       
-       default:
-               AST_RuntimeError(NULL, "Unknown type %i in Object_Dump", Value->Type);
-               return NULL;
+               tAST_Variable   *nextVar = bs.FirstVar->Next;
+               Variable_Destroy( bs.FirstVar );
+               bs.FirstVar = nextVar;
        }
-       
+       return ret;
 }
 
 /**
  * \brief Execute a script function
  * \param Script       Script context to execute in
+ * \param Namespace    Namespace to search for the function
  * \param Function     Function name to execute
  * \param NArguments   Number of arguments to pass
  * \param Arguments    Arguments passed
@@ -355,61 +88,29 @@ tSpiderValue *SpiderScript_ExecuteFunction(tSpiderScript *Script,
        tSpiderNamespace *Namespace, const char *Function,
        int NArguments, tSpiderValue **Arguments)
 {
-       char    *trueName = NULL;
         int    bFound = 0;     // Used to keep nesting levels down
        tSpiderValue    *ret = ERRPTR;
-       tSpiderFunction *fcn;
        
        // First: Find the function in the script
        {
-               tAST_Function   *astFcn;
-               for( astFcn = Script->Script->Functions; astFcn; astFcn = astFcn->Next )
+               tScript_Function        *fcn;
+               for( fcn = Script->Functions; fcn; fcn = fcn->Next )
                {
-                       if( strcmp(astFcn->Name, Function) == 0 )
+                       if( strcmp(fcn->Name, Function) == 0 )
                                break;
                }
                // Execute!
-               if(astFcn)
+               if(fcn)
                {
-                       tAST_BlockState bs;
-                       tAST_Node       *arg;
-                        int    i = 0;
-                       
-                       // Build a block State
-                       bs.FirstVar = NULL;
-                       bs.RetVal = NULL;
-                       bs.Parent = NULL;
-                       bs.BaseNamespace = &Script->Variant->RootNamespace;
-                       bs.CurNamespace = NULL;
-                       bs.Script = Script;
-                       
-                       
-                       for( arg = astFcn->Arguments; arg; arg = arg->NextSibling, i++ )
-                       {
-                               // TODO: Type checks
-                               Variable_Define(&bs, arg->DefVar.DataType, arg->DefVar.Name);
-                               if( i >= NArguments )   break;  // TODO: Return gracefully
-                               Variable_SetValue(&bs, arg->DefVar.Name, Arguments[i]);
-                       }
-                       
-                       // Execute function
-                       ret = AST_ExecuteNode(&bs, astFcn->Code);
-                       Object_Dereference(ret);        // Dereference output of last block statement
-                       ret = bs.RetVal;        // Set to return value of block
+                       ret = AST_ExecuteFunction(Script, fcn, NArguments, Arguments);
                        bFound = 1;
-                       
-                       while(bs.FirstVar)
-                       {
-                               tAST_Variable   *nextVar = bs.FirstVar->Next;
-                               Variable_Destroy( bs.FirstVar );
-                               bs.FirstVar = nextVar;
-                       }
                }
        }
        
        // Didn't find it in script?
        if(!bFound)
        {
+               tSpiderFunction *fcn;
                fcn = NULL;     // Just to allow the below code to be neat
                
                // Second: Scan current namespace
@@ -454,7 +155,8 @@ tSpiderValue *SpiderScript_ExecuteFunction(tSpiderScript *Script,
        // Not found?
        if(!bFound)
        {
-               fprintf(stderr, "Undefined reference to '%s'\n", trueName);
+               fprintf(stderr, "Undefined reference to function '%s' (ns='%s')\n",
+                       Function, Namespace->Name);
                return ERRPTR;
        }
        
@@ -464,12 +166,13 @@ tSpiderValue *SpiderScript_ExecuteFunction(tSpiderScript *Script,
 /**
  * \brief Execute an object method function
  * \param Script       Script context to execute in
- * \param Function     Function name to execute
+ * \param Object       Object in which to find the method
+ * \param MethodName   Name of method to call
  * \param NArguments   Number of arguments to pass
  * \param Arguments    Arguments passed
  */
-tSpiderValue *SpiderScript_ExecuteMethod(tSpiderScript *Script, tSpiderObject *Object,
-       const char *MethodName,
+tSpiderValue *SpiderScript_ExecuteMethod(tSpiderScript *Script,
+       tSpiderObject *Object, const char *MethodName,
        int NArguments, tSpiderValue **Arguments)
 {
        tSpiderFunction *fcn;
@@ -477,12 +180,15 @@ tSpiderValue *SpiderScript_ExecuteMethod(tSpiderScript *Script, tSpiderObject *O
        tSpiderValue    *newargs[NArguments+1];
         int    i;
        
+       // TODO: Support program defined objects
+       
+       // Search for the function
        for( fcn = Object->Type->Methods; fcn; fcn = fcn->Next )
        {
                if( strcmp(fcn->Name, MethodName) == 0 )
                        break;
        }
-       
+       // Error
        if( !fcn )
        {
                AST_RuntimeError(NULL, "Class '%s' does not have a method '%s'",
@@ -490,19 +196,20 @@ tSpiderValue *SpiderScript_ExecuteMethod(tSpiderScript *Script, tSpiderObject *O
                return ERRPTR;
        }
        
+       // Create the "this" argument
        this.Type = SS_DATATYPE_OBJECT;
        this.ReferenceCount = 1;
        this.Object = Object;
-       
        newargs[0] = &this;
        memcpy(&newargs[1], Arguments, NArguments*sizeof(tSpiderValue*));
        
-       // TODO: Type Checking
+       // Check the type of the arguments
        for( i = 0; fcn->ArgTypes[i]; i ++ )
        {
                if( i >= NArguments ) {
-                       AST_RuntimeError(NULL, "Argument count mismatch (%i passed)",
-                               NArguments);
+                       for( ; fcn->ArgTypes[i]; i ++ ) ;
+                       AST_RuntimeError(NULL, "Argument count mismatch (%i passed, %i expected)",
+                               NArguments, i);
                        return ERRPTR;
                }
                if( Arguments[i] && Arguments[i]->Type != fcn->ArgTypes[i] )
@@ -513,6 +220,7 @@ tSpiderValue *SpiderScript_ExecuteMethod(tSpiderScript *Script, tSpiderObject *O
                }
        }
        
+       // Call handler
        return fcn->Handler(Script, NArguments+1, newargs);
 }
 
@@ -532,7 +240,7 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
        tSpiderObjectDef        *class;
        
        // First: Find the function in the script
-       // TODO: Implement scripted classes
+       // TODO: Implement script-defined classes
        #if 0
        {
                tAST_Function   *astClass;
@@ -555,20 +263,24 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
                        bs.BaseNamespace = &Script->Variant->RootNamespace;
                        bs.CurNamespace = NULL;
                        bs.Script = Script;
-                       
+                       bs.Ident = giNextBlockIdent ++;
                        
                        for( arg = astFcn->Arguments; arg; arg = arg->NextSibling, i++ )
                        {
-                               // TODO: Type checks
-                               Variable_Define(&bs, arg->DefVar.DataType, arg->DefVar.Name);
                                if( i >= NArguments )   break;  // TODO: Return gracefully
-                               Variable_SetValue(&bs, arg->DefVar.Name, Arguments[i]);
+                               // TODO: Type checks
+                               Variable_Define(&bs,
+                                       arg->DefVar.DataType, arg->DefVar.Name,
+                                       Arguments[i]);
                        }
                        
                        // Execute function
                        ret = AST_ExecuteNode(&bs, astFcn->Code);
-                       Object_Dereference(ret);        // Dereference output of last block statement
-                       ret = bs.RetVal;        // Set to return value of block
+                       if( ret != ERRPTR )
+                       {
+                               SpiderScript_DereferenceValue(ret);     // Dereference output of last block statement
+                               ret = bs.RetVal;        // Set to return value of block
+                       }
                        bFound = 1;
                        
                        while(bs.FirstVar)
@@ -586,6 +298,9 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
        {
                class = NULL;   // Just to allow the below code to be neat
                
+               //if( !Namespace )
+               //      Namespace = &Script->Variant->RootNamespace;
+               
                // Second: Scan current namespace
                if( !class && Namespace )
                {
@@ -625,10 +340,13 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
                {
                        tSpiderObject   *obj;
                        // TODO: Type Checking
+                       
+                       // Call constructor
                        obj = class->Constructor( NArguments, Arguments );
                        if( obj == NULL || obj == ERRPTR )
                                return (void *)obj;
                        
+                       // Creatue return object
                        ret = malloc( sizeof(tSpiderValue) );
                        ret->Type = SS_DATATYPE_OBJECT;
                        ret->ReferenceCount = 1;
@@ -640,7 +358,7 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
        // Not found?
        if(!bFound)
        {
-               fprintf(stderr, "Undefined reference to '%s'\n", ClassName);
+               fprintf(stderr, "Undefined reference to class '%s'\n", ClassName);
                return ERRPTR;
        }
        
@@ -650,6 +368,8 @@ tSpiderValue *SpiderScript_CreateObject(tSpiderScript *Script,
 
 /**
  * \brief Execute an AST node and return its value
+ * \param Block        Execution context
+ * \param Node Node to execute
  */
 tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
 {
@@ -657,31 +377,36 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
        tSpiderValue    *ret = NULL, *tmpobj;
        tSpiderValue    *op1, *op2;     // Binary operations
         int    cmp;    // Used in comparisons
-        int    i=0;
+        int    i;
        
        switch(Node->Type)
        {
        // No Operation
-       case NODETYPE_NOP:      ret = NULL;     break;
+       case NODETYPE_NOP:
+               ret = NULL;
+               break;
        
        // Code block
        case NODETYPE_BLOCK:
                {
                        tAST_BlockState blockInfo;
-                       memcpy(&blockInfo, Block, sizeof(tAST_BlockState));
+                       blockInfo.Parent = Block;
+                       blockInfo.Script = Block->Script;
                        blockInfo.FirstVar = NULL;
                        blockInfo.RetVal = NULL;
-                       blockInfo.Parent = Block;
+                       blockInfo.BaseNamespace = Block->BaseNamespace;
+                       blockInfo.CurNamespace = NULL;
+                       blockInfo.BreakTarget = NULL;
+                       blockInfo.Ident = giNextBlockIdent ++;
                        ret = NULL;
-                       for(node = Node->Block.FirstChild; node && !blockInfo.RetVal; node = node->NextSibling )
+                       // Loop over all nodes, or until the return value is set
+                       for(node = Node->Block.FirstChild;
+                               node && !blockInfo.RetVal && !blockInfo.BreakTarget;
+                               node = node->NextSibling )
                        {
-                               tmpobj = AST_ExecuteNode(&blockInfo, node);
-                               if(tmpobj == ERRPTR) {  // Error check
-                                       ret = ERRPTR;
-                                       break ;
-                               }
-                               if(tmpobj)      Object_Dereference(tmpobj);     // Free unused value
-                               tmpobj = NULL;
+                               ret = AST_ExecuteNode(&blockInfo, node);
+                               if(ret == ERRPTR)       break;  // Error check
+                               if(ret != NULL) SpiderScript_DereferenceValue(ret);     // Free unused value
                        }
                        // Clean up variables
                        while(blockInfo.FirstVar)
@@ -690,166 +415,276 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                                Variable_Destroy( blockInfo.FirstVar );
                                blockInfo.FirstVar = nextVar;
                        }
+                       // Clear ret if not an error
+                       if(ret != ERRPTR)       ret = NULL;
                        
+                       // Set parent's return value if needed
                        if( blockInfo.RetVal )
                                Block->RetVal = blockInfo.RetVal;
+                       if( blockInfo.BreakTarget ) {
+                               Block->BreakTarget = blockInfo.BreakTarget;
+                               Block->BreakType = blockInfo.BreakType;
+                       }
+                       
+                       // TODO: Unset break if break type deontes a block break
                }
                
                break;
        
        // Assignment
        case NODETYPE_ASSIGN:
+               // TODO: Support assigning to object attributes
                if( Node->Assign.Dest->Type != NODETYPE_VARIABLE ) {
                        AST_RuntimeError(Node, "LVALUE of assignment is not a variable");
                        return ERRPTR;
                }
                ret = AST_ExecuteNode(Block, Node->Assign.Value);
-               if(ret == ERRPTR)
-                       return ERRPTR;
+               if(ret == ERRPTR)       return ERRPTR;
                
+               // Perform assignment operation
                if( Node->Assign.Operation != NODETYPE_NOP )
                {
-                       tSpiderValue    *varVal = Variable_GetValue(Block, Node->Assign.Dest->Variable.Name);
-                       tSpiderValue    *value;
-                       value = AST_ExecuteNode_BinOp(Block, Node->Assign.Operation, varVal, ret);
-                       if( value == ERRPTR )
-                               return ERRPTR;
-                       if(ret) Object_Dereference(ret);
-                       Object_Dereference(varVal);
+                       tSpiderValue    *varVal, *value;
+
+                       varVal = Variable_GetValue(Block, Node->Assign.Dest);
+                       if(varVal == ERRPTR)    return ERRPTR;
+                       #if 0
+                       #else
+                       if(varVal && varVal->ReferenceCount == 2) {
+                               SpiderScript_DereferenceValue(varVal);
+//                             printf("pre: (%s) varVal->ReferenceCount = %i\n",
+//                                     Node->Assign.Dest->Variable.Name,
+//                                     varVal->ReferenceCount);
+                       }
+                       #endif
+                       value = AST_ExecuteNode_BinOp(Block->Script, Node, Node->Assign.Operation, varVal, ret);
+                       if(value == ERRPTR)     return ERRPTR;
+
+                       if(ret) SpiderScript_DereferenceValue(ret);
+                       #if 0
+                       if(varVal)      SpiderScript_DereferenceValue(varVal);
+                       #else
+                       if(varVal && varVal->ReferenceCount == 1) {
+                               SpiderScript_ReferenceValue(varVal);
+//                             printf("post: varVal->ReferenceCount = %i\n", varVal->ReferenceCount);
+                               break;  // If varVal was non-null, it has been updated by _BinOp
+                       }
+                       #endif
+                       // Else, it was NULL, so has to be assigned
                        ret = value;
                }
                
-               if( Variable_SetValue( Block, Node->Assign.Dest->Variable.Name, ret ) ) {
-                       Object_Dereference( ret );
+               // Set the variable value
+               if( Variable_SetValue( Block, Node->Assign.Dest, ret ) ) {
+                       SpiderScript_DereferenceValue( ret );
                        return ERRPTR;
                }
                break;
        
+       // Post increment/decrement
+       case NODETYPE_POSTINC:
+       case NODETYPE_POSTDEC:
+               {
+                       tSpiderValue    *varVal, *value;
+                       static tSpiderValue     one = {
+                               .Type = SS_DATATYPE_INTEGER,
+                               .ReferenceCount = 1,
+                               {.Integer = 1}
+                               };
+                       
+                       // TODO: Support assigning to object attributes
+                       if( Node->UniOp.Value->Type != NODETYPE_VARIABLE ) {
+                               AST_RuntimeError(Node, "LVALUE of assignment is not a variable");
+                               return ERRPTR;
+                       }
+               
+                       // Get values (current variable contents and a static one)
+                       varVal = Variable_GetValue(Block, Node->UniOp.Value);
+                       
+                       if( Node->Type == NODETYPE_POSTDEC )
+                               value = AST_ExecuteNode_BinOp(Block->Script, Node, NODETYPE_SUBTRACT, varVal, &one);
+                       else
+                               value = AST_ExecuteNode_BinOp(Block->Script, Node, NODETYPE_ADD, varVal, &one);
+                       if( value == ERRPTR )
+                               return ERRPTR;
+                       
+                       ret = varVal;
+               
+                       if( Variable_SetValue( Block, Node->UniOp.Value, value ) ) {
+                               SpiderScript_DereferenceValue( ret );
+                               return ERRPTR;
+                       }
+                       SpiderScript_DereferenceValue( value );
+               }
+               break;
+       
        // Function Call
        case NODETYPE_METHODCALL:
        case NODETYPE_FUNCTIONCALL:
        case NODETYPE_CREATEOBJECT:
+               // Logical block (used to allocate `params`)
                {
-                        int    nParams = 0;
-                       for(node = Node->FunctionCall.FirstArg; node; node = node->NextSibling) {
-                               nParams ++;
-                       }
-                       // Logical block (used to allocate `params`)
+                       tSpiderNamespace        *ns = Block->CurNamespace;
+                       tSpiderValue    *params[Node->FunctionCall.NumArgs];
+                       i = 0;
+                       for(node = Node->FunctionCall.FirstArg; node; node = node->NextSibling)
                        {
-                               tSpiderValue    *params[nParams];
-                               i = 0;
-                               for(node = Node->FunctionCall.FirstArg; node; node = node->NextSibling)
-                               {
-                                       params[i] = AST_ExecuteNode(Block, node);
-                                       if( params[i] == ERRPTR ) {
-                                               while(i--)      Object_Dereference(params[i]);
-                                               ret = ERRPTR;
-                                               goto _return;
-                                       }
-                                       i ++;
-                               }
-                               
-                               if( !Block->CurNamespace )
-                                       Block->CurNamespace = Block->BaseNamespace;
-                               
-                               // Call the function
-                               if( Node->Type == NODETYPE_CREATEOBJECT )
-                               {
-                                       ret = SpiderScript_CreateObject(Block->Script,
-                                               Block->CurNamespace,
-                                               Node->FunctionCall.Name,
-                                               nParams, params
-                                               );
-                               }
-                               else if( Node->Type == NODETYPE_METHODCALL )
-                               {
-                                       tSpiderValue *obj = AST_ExecuteNode(Block, Node->FunctionCall.Object);
-                                       if( !obj || obj->Type != SS_DATATYPE_OBJECT ) {
-                                               AST_RuntimeError(Node->FunctionCall.Object,
-                                                       "Type Mismatch - Required SS_DATATYPE_OBJECT for method call");
-                                               while(i--)      Object_Dereference(params[i]);
-                                               ret = ERRPTR;
-                                               break;
-                                       }
-                                       ret = SpiderScript_ExecuteMethod(Block->Script,
-                                               obj->Object, Node->FunctionCall.Name,
-                                               nParams, params
-                                               );
-                                       Object_Dereference(obj);
+                               params[i] = AST_ExecuteNode(Block, node);
+                               if( params[i] == ERRPTR ) {
+                                       while(i--)      SpiderScript_DereferenceValue(params[i]);
+                                       ret = ERRPTR;
+                                       goto _return;
                                }
-                               else
-                               {
-                                       ret = SpiderScript_ExecuteFunction(Block->Script,
-                                               Block->CurNamespace, Node->FunctionCall.Name,
-                                               nParams, params
-                                               );
+                               i ++;
+                       }
+                       
+                       if( !ns )       ns = Block->BaseNamespace;
+                       
+                       // Call the function
+                       if( Node->Type == NODETYPE_CREATEOBJECT )
+                       {
+                               ret = SpiderScript_CreateObject(Block->Script,
+                                       ns,
+                                       Node->FunctionCall.Name,
+                                       Node->FunctionCall.NumArgs, params
+                                       );
+                       }
+                       else if( Node->Type == NODETYPE_METHODCALL )
+                       {
+                               tSpiderValue *obj = AST_ExecuteNode(Block, Node->FunctionCall.Object);
+                               if( !obj || obj == ERRPTR || obj->Type != SS_DATATYPE_OBJECT ) {
+                                       AST_RuntimeError(Node->FunctionCall.Object,
+                                               "Type Mismatch - Required SS_DATATYPE_OBJECT for method call");
+                                       while(i--)      SpiderScript_DereferenceValue(params[i]);
+                                       ret = ERRPTR;
+                                       break;
                                }
-
-                               
-                               // Dereference parameters
-                               while(i--)      Object_Dereference(params[i]);
-                               
-                               // falls out
+                               ret = SpiderScript_ExecuteMethod(Block->Script,
+                                       obj->Object, Node->FunctionCall.Name,
+                                       Node->FunctionCall.NumArgs, params
+                                       );
+                               SpiderScript_DereferenceValue(obj);
+                       }
+                       else
+                       {
+                               ret = SpiderScript_ExecuteFunction(Block->Script,
+                                       ns, Node->FunctionCall.Name,
+                                       Node->FunctionCall.NumArgs, params
+                                       );
                        }
+
+                       
+                       // Dereference parameters
+                       while(i--)      SpiderScript_DereferenceValue(params[i]);
+                       
+                       // falls out
                }
                break;
        
        // Conditional
        case NODETYPE_IF:
                ret = AST_ExecuteNode(Block, Node->If.Condition);
+               if( ret == ERRPTR )     break;
                if( SpiderScript_IsValueTrue(ret) ) {
-                       Object_Dereference(AST_ExecuteNode(Block, Node->If.True));
+                       tmpobj = AST_ExecuteNode(Block, Node->If.True);
                }
                else {
-                       Object_Dereference(AST_ExecuteNode(Block, Node->If.False));
+                       tmpobj = AST_ExecuteNode(Block, Node->If.False);
                }
-               Object_Dereference(ret);
+               SpiderScript_DereferenceValue(ret);
+               if( tmpobj == ERRPTR )  return ERRPTR;
+               SpiderScript_DereferenceValue(tmpobj);
                ret = NULL;
                break;
        
        // Loop
        case NODETYPE_LOOP:
+               // Initialise
                ret = AST_ExecuteNode(Block, Node->For.Init);
-               if( Node->For.bCheckAfter )
+               if(ret == ERRPTR)       break;
+               
+               // Check initial condition
+               if( !Node->For.bCheckAfter )
                {
-                       do {
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Code);
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Increment);
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Condition);
-                       } while( SpiderScript_IsValueTrue(ret) );
+                       SpiderScript_DereferenceValue(ret);
+               
+                       ret = AST_ExecuteNode(Block, Node->For.Condition);
+                       if(ret == ERRPTR)       return ERRPTR;
+                       if(!SpiderScript_IsValueTrue(ret)) {
+                               SpiderScript_DereferenceValue(ret);
+                               ret = NULL;
+                               break;
+                       }
                }
-               else
+       
+               // Perform loop
+               for( ;; )
                {
-                       Object_Dereference(ret);
-                       ret = AST_ExecuteNode(Block, Node->For.Condition);
-                       while( SpiderScript_IsValueTrue(ret) ) {
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Code);
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Increment);
-                               Object_Dereference(ret);
-                               ret = AST_ExecuteNode(Block, Node->For.Condition);
+                       SpiderScript_DereferenceValue(ret);
+                       
+                       // Code
+                       ret = AST_ExecuteNode(Block, Node->For.Code);
+                       if(ret == ERRPTR)       return ERRPTR;
+                       SpiderScript_DereferenceValue(ret);
+                       
+                       if(Block->BreakTarget)
+                       {
+                               if( Block->BreakTarget[0] == '\0' || strcmp(Block->BreakTarget, Node->For.Tag) == 0 )
+                               {
+                                       // Ours
+                                       free((void*)Block->BreakTarget);        Block->BreakTarget = NULL;
+                                       if( Block->BreakType == NODETYPE_CONTINUE ) {
+                                               // Continue, just keep going
+                                       }
+                                       else
+                                               break;
+                               }
+                               else
+                                       break;  // Break out of this loop
                        }
+                       
+                       // Increment
+                       ret = AST_ExecuteNode(Block, Node->For.Increment);
+                       if(ret == ERRPTR)       return ERRPTR;
+                       SpiderScript_DereferenceValue(ret);
+                       
+                       // Check condition
+                       ret = AST_ExecuteNode(Block, Node->For.Condition);
+                       if(ret == ERRPTR)       return ERRPTR;
+                       if(!SpiderScript_IsValueTrue(ret))      break;
                }
-               Object_Dereference(ret);
+               SpiderScript_DereferenceValue(ret);
                ret = NULL;
                break;
        
        // Return
        case NODETYPE_RETURN:
                ret = AST_ExecuteNode(Block, Node->UniOp.Value);
+               if(ret == ERRPTR)       break;
                Block->RetVal = ret;    // Return value set
                ret = NULL;     // the `return` statement does not return a value
                break;
        
+       case NODETYPE_BREAK:
+       case NODETYPE_CONTINUE:
+               Block->BreakTarget = strdup(Node->Variable.Name);
+               Block->BreakType = Node->Type;
+               break;
+       
        // Define a variable
        case NODETYPE_DEFVAR:
+               if( Node->DefVar.InitialValue ) {
+                       tmpobj = AST_ExecuteNode(Block, Node->DefVar.InitialValue);
+                       if(tmpobj == ERRPTR)    return ERRPTR;
+               }
+               else {
+                       tmpobj = NULL;
+               }
+               // TODO: Handle arrays
                ret = NULL;
-               if( Variable_Define(Block, Node->DefVar.DataType, Node->DefVar.Name) == ERRPTR )
+               if( Variable_Define(Block, Node->DefVar.DataType, Node->DefVar.Name, tmpobj) == ERRPTR )
                        ret = ERRPTR;
+               SpiderScript_DereferenceValue(tmpobj);
                break;
        
        // Scope
@@ -888,13 +723,14 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
        
        // Variable
        case NODETYPE_VARIABLE:
-               ret = Variable_GetValue( Block, Node->Variable.Name );
+               ret = Variable_GetValue( Block, Node );
                break;
        
        // Element of an Object
        case NODETYPE_ELEMENT:
                tmpobj = AST_ExecuteNode( Block, Node->Scope.Element );
-               if( tmpobj->Type != SS_DATATYPE_OBJECT )
+               if(tmpobj == ERRPTR)    return ERRPTR;
+               if( !tmpobj || tmpobj->Type != SS_DATATYPE_OBJECT )
                {
                        AST_RuntimeError(Node->Scope.Element, "Unable to dereference a non-object");
                        ret = ERRPTR;
@@ -906,7 +742,7 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                        if( strcmp(Node->Scope.Name, tmpobj->Object->Type->AttributeDefs[i].Name) == 0 )
                        {
                                ret = tmpobj->Object->Attributes[i];
-                               Object_Reference(ret);
+                               SpiderScript_ReferenceValue(ret);
                                break;
                        }
                }
@@ -922,17 +758,23 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
        case NODETYPE_CAST:
                {
                tmpobj = AST_ExecuteNode(Block, Node->Cast.Value);
+               if(tmpobj == ERRPTR) return ERRPTR;
                ret = SpiderScript_CastValueTo( Node->Cast.DataType, tmpobj );
-               Object_Dereference(tmpobj);
+               SpiderScript_DereferenceValue(tmpobj);
                }
                break;
 
        // Index into an array
        case NODETYPE_INDEX:
                op1 = AST_ExecuteNode(Block, Node->BinOp.Left); // Array
+               if(op1 == ERRPTR)       return ERRPTR;
                op2 = AST_ExecuteNode(Block, Node->BinOp.Right);        // Offset
+               if(op2 == ERRPTR) {
+                       SpiderScript_DereferenceValue(op1);
+                       return ERRPTR;
+               }
                
-               if( op1->Type != SS_DATATYPE_ARRAY )
+               if( !op1 || op1->Type != SS_DATATYPE_ARRAY )
                {
                        // TODO: Implement "operator []" on objects
                        AST_RuntimeError(Node, "Indexing non-array");
@@ -940,16 +782,16 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                        break;
                }
                
-               if( op2->Type != SS_DATATYPE_INTEGER && !Block->Script->Variant->bImplicitCasts ) {
+               if( (!op2 || op2->Type != SS_DATATYPE_INTEGER) && !Block->Script->Variant->bImplicitCasts ) {
                        AST_RuntimeError(Node, "Array index is not an integer");
                        ret = ERRPTR;
                        break;
                }
                
-               if( op2->Type != SS_DATATYPE_INTEGER )
+               if( !op2 || op2->Type != SS_DATATYPE_INTEGER )
                {
                        tmpobj = SpiderScript_CastValueTo(SS_DATATYPE_INTEGER, op2);
-                       Object_Dereference(op2);
+                       SpiderScript_DereferenceValue(op2);
                        op2 = tmpobj;
                }
                
@@ -961,26 +803,35 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                }
                
                ret = op1->Array.Items[ op2->Integer ];
-               Object_Reference(ret);
+               SpiderScript_ReferenceValue(ret);
                
-               Object_Dereference(op1);
-               Object_Dereference(op2);
+               SpiderScript_DereferenceValue(op1);
+               SpiderScript_DereferenceValue(op2);
                break;
 
        // TODO: Implement runtime constants
        case NODETYPE_CONSTANT:
-               // TODO: Scan namespace for function
+               // TODO: Scan namespace for constant name
                AST_RuntimeError(Node, "TODO - Runtime Constants");
                ret = ERRPTR;
                break;
        
        // Constant Values
-       case NODETYPE_STRING:   ret = SpiderScript_CreateString( Node->String.Length, Node->String.Data );      break;
-       case NODETYPE_INTEGER:  ret = SpiderScript_CreateInteger( Node->Integer );      break;
-       case NODETYPE_REAL:     ret = SpiderScript_CreateReal( Node->Real );    break;
+       case NODETYPE_STRING:
+       case NODETYPE_INTEGER:
+       case NODETYPE_REAL:
+               ret = &Node->Constant;
+               SpiderScript_ReferenceValue(ret);
+               break;
        
        // --- Operations ---
        // Boolean Operations
+       case NODETYPE_LOGICALNOT:       // Logical NOT (!)
+               op1 = AST_ExecuteNode(Block, Node->UniOp.Value);
+               if(op1 == ERRPTR)       return ERRPTR;
+               ret = SpiderScript_CreateInteger( !SpiderScript_IsValueTrue(op1) );
+               SpiderScript_DereferenceValue(op1);
+               break;
        case NODETYPE_LOGICALAND:       // Logical AND (&&)
        case NODETYPE_LOGICALOR:        // Logical OR (||)
        case NODETYPE_LOGICALXOR:       // Logical XOR (^^)
@@ -988,7 +839,7 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                if(op1 == ERRPTR)       return ERRPTR;
                op2 = AST_ExecuteNode(Block, Node->BinOp.Right);
                if(op2 == ERRPTR) {
-                       Object_Dereference(op1);
+                       SpiderScript_DereferenceValue(op1);
                        return ERRPTR;
                }
                
@@ -1007,38 +858,50 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                }
                
                // Free intermediate objects
-               Object_Dereference(op1);
-               Object_Dereference(op2);
+               SpiderScript_DereferenceValue(op1);
+               SpiderScript_DereferenceValue(op2);
                break;
        
        // Comparisons
        case NODETYPE_EQUALS:
        case NODETYPE_LESSTHAN:
        case NODETYPE_GREATERTHAN:
+       case NODETYPE_LESSTHANEQUAL:
+       case NODETYPE_GREATERTHANEQUAL:
                op1 = AST_ExecuteNode(Block, Node->BinOp.Left);
                if(op1 == ERRPTR)       return ERRPTR;
                op2 = AST_ExecuteNode(Block, Node->BinOp.Right);
                if(op2 == ERRPTR) {
-                       Object_Dereference(op1);
-                       return ERRPTR;
+                       SpiderScript_DereferenceValue(op1);
+                       ret = ERRPTR;
+                       break;
+               }
+               
+               if( !op1 || !op2 ) {
+                       AST_RuntimeError(Node, "NULL Comparison (%p and %p)", op1, op2);
+                       if(op1) SpiderScript_DereferenceValue(op1);
+                       if(op2) SpiderScript_DereferenceValue(op2);
+                       ret = SpiderScript_CreateInteger( !op1 && !op2 );
+                       break;
                }
                
                // Convert types
                if( op1->Type != op2->Type ) {
                        // If dynamically typed, convert op2 to op1's type
-                       if(Block->Script->Variant->bDyamicTyped)
+                       if(Block->Script->Variant->bImplicitCasts)
                        {
                                tmpobj = op2;
                                op2 = SpiderScript_CastValueTo(op1->Type, op2);
-                               Object_Dereference(tmpobj);
+                               SpiderScript_DereferenceValue(tmpobj);
                                if(op2 == ERRPTR) {
-                                       Object_Dereference(op1);
+                                       SpiderScript_DereferenceValue(op1);
                                        return ERRPTR;
                                }
                        }
                        // If statically typed, this should never happen, but catch it anyway
                        else {
-                               AST_RuntimeError(Node, "Statically typed implicit cast");
+                               AST_RuntimeError(Node, "Statically typed implicit cast %i <op> %i",
+                                       op1->Type, op2->Type);
                                ret = ERRPTR;
                                break;
                        }
@@ -1073,6 +936,10 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                        else
                                cmp = 1;
                        break;
+               // - Real Number Comparisons
+               case SS_DATATYPE_REAL:
+                       cmp = (op1->Real - op2->Real) / op2->Real * 10000;      // < 0.1% difference is equality
+                       break;
                default:
                        AST_RuntimeError(Node, "TODO - Comparison of type %i", op1->Type);
                        ret = ERRPTR;
@@ -1080,8 +947,8 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                }
                
                // Free intermediate objects
-               Object_Dereference(op1);
-               Object_Dereference(op2);
+               SpiderScript_DereferenceValue(op1);
+               SpiderScript_DereferenceValue(op2);
                
                // Error check
                if( ret == ERRPTR )
@@ -1093,6 +960,8 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                case NODETYPE_EQUALS:   ret = SpiderScript_CreateInteger(cmp == 0);     break;
                case NODETYPE_LESSTHAN: ret = SpiderScript_CreateInteger(cmp < 0);      break;
                case NODETYPE_GREATERTHAN:      ret = SpiderScript_CreateInteger(cmp > 0);      break;
+               case NODETYPE_LESSTHANEQUAL:    ret = SpiderScript_CreateInteger(cmp <= 0);     break;
+               case NODETYPE_GREATERTHANEQUAL: ret = SpiderScript_CreateInteger(cmp >= 0);     break;
                default:
                        AST_RuntimeError(Node, "Exec,CmpOp unknown op %i", Node->Type);
                        ret = ERRPTR;
@@ -1100,6 +969,15 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                }
                break;
        
+       // General Unary Operations
+       case NODETYPE_BWNOT:    // Bitwise NOT (~)
+       case NODETYPE_NEGATE:   // Negation (-)
+               op1 = AST_ExecuteNode(Block, Node->UniOp.Value);
+               if(op1 == ERRPTR)       return ERRPTR;
+               ret = AST_ExecuteNode_UniOp(Block->Script, Node, Node->Type, op1);
+               SpiderScript_DereferenceValue(op1);
+               break;
+       
        // General Binary Operations
        case NODETYPE_ADD:
        case NODETYPE_SUBTRACT:
@@ -1117,27 +995,102 @@ tSpiderValue *AST_ExecuteNode(tAST_BlockState *Block, tAST_Node *Node)
                if(op1 == ERRPTR)       return ERRPTR;
                op2 = AST_ExecuteNode(Block, Node->BinOp.Right);
                if(op2 == ERRPTR) {
-                       Object_Dereference(op1);
+                       SpiderScript_DereferenceValue(op1);
                        return ERRPTR;
                }
                
-               ret = AST_ExecuteNode_BinOp(Block, Node->Type, op1, op2);
+               ret = AST_ExecuteNode_BinOp(Block->Script, Node, Node->Type, op1, op2);
                
                // Free intermediate objects
-               Object_Dereference(op1);
-               Object_Dereference(op2);
+               SpiderScript_DereferenceValue(op1);
+               SpiderScript_DereferenceValue(op2);
                break;
        
        //default:
        //      ret = NULL;
-       //      AST_RuntimeError(Node, "BUG - SpiderScript AST_ExecuteNode Unimplemented %i\n", Node->Type);
+       //      AST_RuntimeError(Node, "BUG - SpiderScript AST_ExecuteNode Unimplemented %i", Node->Type);
        //      break;
        }
 _return:
+       // Reset namespace when no longer needed
+       if( Node->Type != NODETYPE_SCOPE )
+               Block->CurNamespace = NULL;
+
+       #if TRACE_NODE_RETURNS
+       if(ret && ret != ERRPTR) {
+               AST_RuntimeError(Node, "Ret type of %p %i is %i", Node, Node->Type, ret->Type);
+       }
+       else {
+               AST_RuntimeError(Node, "Ret type of %p %i is %p", Node, Node->Type, ret);
+       }
+       #endif
+
        return ret;
 }
 
-tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpiderValue *Left, tSpiderValue *Right)
+tSpiderValue *AST_ExecuteNode_UniOp(tSpiderScript *Script, tAST_Node *Node, int Operation, tSpiderValue *Value)
+{
+       tSpiderValue    *ret;
+       #if 0
+       if( Value->Type == SS_DATATYPE_OBJECT )
+       {
+               const char      *fcnname;
+               switch(Operation)
+               {
+               case NODETYPE_NEGATE:   fcnname = "-ve";        break;
+               case NODETYPE_BWNOT:    fcnname = "~";  break;
+               default:        fcnname = NULL; break;
+               }
+               
+               if( fcnname )
+               {
+                       ret = Object_ExecuteMethod(Value->Object, fcnname, );
+                       if( ret != ERRPTR )
+                               return ret;
+               }
+       }
+       #endif
+       switch(Value->Type)
+       {
+       // Integer Operations
+       case SS_DATATYPE_INTEGER:
+               if( Value->ReferenceCount == 1 )
+                       SpiderScript_ReferenceValue(ret = Value);
+               else
+                       ret = SpiderScript_CreateInteger(0);
+               switch(Operation)
+               {
+               case NODETYPE_NEGATE:   ret->Integer = -Value->Integer; break;
+               case NODETYPE_BWNOT:    ret->Integer = ~Value->Integer; break;
+               default:
+                       AST_RuntimeError(Node, "SpiderScript internal error: Exec,UniOP,Integer unknown op %i", Operation);
+                       SpiderScript_DereferenceValue(ret);
+                       ret = ERRPTR;
+                       break;
+               }
+               break;
+       // Real number Operations
+       case SS_DATATYPE_REAL:
+               switch(Operation)
+               {
+               case NODETYPE_NEGATE:   ret = SpiderScript_CreateInteger( -Value->Real );       break;
+               default:
+                       AST_RuntimeError(Node, "SpiderScript internal error: Exec,UniOP,Real unknown op %i", Operation);
+                       ret = ERRPTR;
+                       break;
+               }
+               break;
+       
+       default:
+               AST_RuntimeError(NULL, "Invalid operation (%i) on type (%i)", Operation, Value->Type);
+               ret = ERRPTR;
+               break;
+       }
+       
+       return ret;
+}
+
+tSpiderValue *AST_ExecuteNode_BinOp(tSpiderScript *Script, tAST_Node *Node, int Operation, tSpiderValue *Left, tSpiderValue *Right)
 {
        tSpiderValue    *preCastValue = Right;
        tSpiderValue    *ret;
@@ -1178,7 +1131,7 @@ tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpid
                #endif
                
                // If implicit casts are allowed, convert Right to Left's type
-               if(Block->Script->Variant->bImplicitCasts)
+               if(Script->Variant->bImplicitCasts)
                {
                        Right = SpiderScript_CastValueTo(Left->Type, Right);
                        if(Right == ERRPTR)
@@ -1186,7 +1139,7 @@ tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpid
                }
                // If statically typed, this should never happen, but catch it anyway
                else {
-                       AST_RuntimeError(NULL, "Implicit cast not allowed (from %i to %i)\n", Right->Type, Left->Type);
+                       AST_RuntimeError(Node, "Implicit cast not allowed (from %i to %i)", Right->Type, Left->Type);
                        return ERRPTR;
                }
        }
@@ -1205,33 +1158,47 @@ tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpid
                switch(Operation)
                {
                case NODETYPE_ADD:      // Concatenate
-                       ret = Object_StringConcat(Left, Right);
+                       ret = SpiderScript_StringConcat(Left, Right);
                        break;
+               // TODO: Support python style 'i = %i' % i ?
+               // Might do it via a function call
+               // Implement it via % with an array, but getting past the cast will be fun
+//             case NODETYPE_MODULUS:
+//                     break;
+               // TODO: Support string repititions
+//             case NODETYPE_MULTIPLY:
+//                     break;
+
                default:
-                       AST_RuntimeError(NULL, "SpiderScript internal error: Exec,BinOP,String unknown op %i", Operation);
+                       AST_RuntimeError(Node, "SpiderScript internal error: Exec,BinOP,String unknown op %i", Operation);
                        ret = ERRPTR;
                        break;
                }
                break;
        // Integer Operations
        case SS_DATATYPE_INTEGER:
+               if( Left->ReferenceCount == 1 )
+                       SpiderScript_ReferenceValue(ret = Left);
+               else
+                       ret = SpiderScript_CreateInteger(0);
                switch(Operation)
                {
-               case NODETYPE_ADD:      ret = SpiderScript_CreateInteger( Left->Integer + Right->Integer );     break;
-               case NODETYPE_SUBTRACT: ret = SpiderScript_CreateInteger( Left->Integer - Right->Integer );     break;
-               case NODETYPE_MULTIPLY: ret = SpiderScript_CreateInteger( Left->Integer * Right->Integer );     break;
-               case NODETYPE_DIVIDE:   ret = SpiderScript_CreateInteger( Left->Integer / Right->Integer );     break;
-               case NODETYPE_MODULO:   ret = SpiderScript_CreateInteger( Left->Integer % Right->Integer );     break;
-               case NODETYPE_BWAND:    ret = SpiderScript_CreateInteger( Left->Integer & Right->Integer );     break;
-               case NODETYPE_BWOR:     ret = SpiderScript_CreateInteger( Left->Integer | Right->Integer );     break;
-               case NODETYPE_BWXOR:    ret = SpiderScript_CreateInteger( Left->Integer ^ Right->Integer );     break;
-               case NODETYPE_BITSHIFTLEFT:     ret = SpiderScript_CreateInteger( Left->Integer << Right->Integer );    break;
-               case NODETYPE_BITSHIFTRIGHT:ret = SpiderScript_CreateInteger( Left->Integer >> Right->Integer );        break;
+               case NODETYPE_ADD:      ret->Integer = Left->Integer + Right->Integer;  break;
+               case NODETYPE_SUBTRACT: ret->Integer = Left->Integer - Right->Integer;  break;
+               case NODETYPE_MULTIPLY: ret->Integer = Left->Integer * Right->Integer;  break;
+               case NODETYPE_DIVIDE:   ret->Integer = Left->Integer / Right->Integer;  break;
+               case NODETYPE_MODULO:   ret->Integer = Left->Integer % Right->Integer;  break;
+               case NODETYPE_BWAND:    ret->Integer = Left->Integer & Right->Integer;  break;
+               case NODETYPE_BWOR:     ret->Integer = Left->Integer | Right->Integer;  break;
+               case NODETYPE_BWXOR:    ret->Integer = Left->Integer ^ Right->Integer;  break;
+               case NODETYPE_BITSHIFTLEFT: ret->Integer = Left->Integer << Right->Integer;     break;
+               case NODETYPE_BITSHIFTRIGHT:ret->Integer = Left->Integer >> Right->Integer;     break;
                case NODETYPE_BITROTATELEFT:
-                       ret = SpiderScript_CreateInteger( (Left->Integer << Right->Integer) | (Left->Integer >> (64-Right->Integer)) );
+                       ret->Integer = (Left->Integer << Right->Integer) | (Left->Integer >> (64-Right->Integer));
                        break;
                default:
-                       AST_RuntimeError(NULL, "SpiderScript internal error: Exec,BinOP,Integer unknown op %i\n", Operation);
+                       AST_RuntimeError(Node, "SpiderScript internal error: Exec,BinOP,Integer unknown op %i", Operation);
+                       SpiderScript_DereferenceValue(ret);
                        ret = ERRPTR;
                        break;
                }
@@ -1239,17 +1206,26 @@ tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpid
        
        // Real Numbers
        case SS_DATATYPE_REAL:
+               if( Left->ReferenceCount == 1 )
+                       SpiderScript_ReferenceValue(ret = Left);
+               else
+                       ret = SpiderScript_CreateReal(0);
                switch(Operation)
                {
+               case NODETYPE_ADD:      ret->Real = Left->Real + Right->Real;   break;
+               case NODETYPE_SUBTRACT: ret->Real = Left->Real - Right->Real;   break;
+               case NODETYPE_MULTIPLY: ret->Real = Left->Real * Right->Real;   break;
+               case NODETYPE_DIVIDE:   ret->Real = Left->Real / Right->Real;   break;
                default:
-                       AST_RuntimeError(NULL, "SpiderScript internal error: Exec,BinOP,Real unknown op %i", Operation);
+                       AST_RuntimeError(Node, "SpiderScript internal error: Exec,BinOP,Real unknown op %i", Operation);
+                       SpiderScript_DereferenceValue(ret);
                        ret = ERRPTR;
                        break;
                }
                break;
        
        default:
-               AST_RuntimeError(NULL, "BUG - Invalid operation (%i) on type (%i)", Operation, Left->Type);
+               AST_RuntimeError(Node, "BUG - Invalid operation (%i) on type (%i)", Operation, Left->Type);
                ret = ERRPTR;
                break;
        }
@@ -1266,7 +1242,7 @@ tSpiderValue *AST_ExecuteNode_BinOp(tAST_BlockState *Block, int Operation, tSpid
  * \param Name Name of the variable
  * \return Boolean Failure
  */
-tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Name)
+tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Name, tSpiderValue *Value)
 {
        tAST_Variable   *var, *prev = NULL;
        
@@ -1281,7 +1257,8 @@ tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Nam
        var = malloc( sizeof(tAST_Variable) + strlen(Name) + 1 );
        var->Next = NULL;
        var->Type = Type;
-       var->Object = NULL;
+       var->Object = Value;
+       if(Value)       SpiderScript_ReferenceValue(Value);
        strcpy(var->Name, Name);
        
        if(prev)        prev->Next = var;
@@ -1292,74 +1269,97 @@ tAST_Variable *Variable_Define(tAST_BlockState *Block, int Type, const char *Nam
        return var;
 }
 
-/**
- * \brief Set the value of a variable
- * \return Boolean Failure
- */
-int Variable_SetValue(tAST_BlockState *Block, const char *Name, tSpiderValue *Value)
-{
-       tAST_Variable   *var;
-       tAST_BlockState *bs;
-       
-       for( bs = Block; bs; bs = bs->Parent )
+tAST_Variable *Variable_Lookup(tAST_BlockState *Block, tAST_Node *VarNode, int CreateType)
+{      
+       tAST_Variable   *var = NULL;
+       
+       // Speed hack
+       if( VarNode->BlockState == Block && VarNode->BlockIdent == Block->Ident ) {
+               var = VarNode->ValueCache;
+               #if TRACE_VAR_LOOKUPS
+               AST_RuntimeMessage(VarNode, "debug", "Fast var fetch on '%s' %p (%p:%i)",
+                       VarNode->Variable.Name, var,
+                       VarNode->BlockState, VarNode->BlockIdent
+                       );
+               #endif
+       }
+       else
        {
-               for( var = bs->FirstVar; var; var = var->Next )
+               tAST_BlockState *bs;
+               for( bs = Block; bs; bs = bs->Parent )
                {
-                       if( strcmp(var->Name, Name) == 0 )
+                       for( var = bs->FirstVar; var; var = var->Next )
                        {
-                               if( !Block->Script->Variant->bDyamicTyped
-                                && (Value && var->Type != Value->Type) )
-                               {
-                                       AST_RuntimeError(NULL, "Type mismatch assigning to '%s'", Name);
-                                       return -2;
-                               }
-//                             printf("Assign %p to '%s'\n", Value, var->Name);
-                               Object_Reference(Value);
-                               Object_Dereference(var->Object);
-                               var->Object = Value;
-                               return 0;
+                               if( strcmp(var->Name, VarNode->Variable.Name) == 0 )
+                                       break;
                        }
+                       if(var) break;
                }
+               
+               if( !var )
+               {
+                       if( Block->Script->Variant->bDyamicTyped && CreateType != SS_DATATYPE_UNDEF ) {
+                               // Define variable
+                               var = Variable_Define(Block, CreateType, VarNode->Variable.Name, NULL);
+                       }
+                       else
+                       {
+                               AST_RuntimeError(VarNode, "Variable '%s' is undefined", VarNode->Variable.Name);
+                               return NULL;
+                       }
+               }
+               
+               #if TRACE_VAR_LOOKUPS
+               AST_RuntimeMessage(VarNode, "debug", "Saved variable lookup of '%s' %p (%p:%i)",
+                       VarNode->Variable.Name, var,
+                       Block, Block->Ident);
+               #endif
+               
+               VarNode->ValueCache = var;
+               VarNode->BlockState = Block;
+               VarNode->BlockIdent = Block->Ident;
        }
        
-       if( Block->Script->Variant->bDyamicTyped )
-       {
-               // Define variable
-               var = Variable_Define(Block, Value->Type, Name);
-               Object_Reference(Value);
-               var->Object = Value;
-               return 0;
-       }
-       else
-       {
-               AST_RuntimeError(NULL, "Variable '%s' set while undefined", Name);
-               return -1;
-       }
+       return var;
 }
 
 /**
- * \brief Get the value of a variable
+ * \brief Set the value of a variable
+ * \return Boolean Failure
  */
-tSpiderValue *Variable_GetValue(tAST_BlockState *Block, const char *Name)
+int Variable_SetValue(tAST_BlockState *Block, tAST_Node *VarNode, tSpiderValue *Value)
 {
        tAST_Variable   *var;
-       tAST_BlockState *bs;
        
-       for( bs = Block; bs; bs = bs->Parent )
+       var = Variable_Lookup(Block, VarNode, (Value ? Value->Type : SS_DATATYPE_UNDEF));
+       
+       if( !var )      return -1;
+       
+       if( !Block->Script->Variant->bDyamicTyped && (Value && var->Type != Value->Type) )
        {
-               for( var = bs->FirstVar; var; var = var->Next )
-               {
-                       if( strcmp(var->Name, Name) == 0 ) {
-                               Object_Reference(var->Object);
-                               return var->Object;
-                       }
-               }
+               AST_RuntimeError(VarNode, "Type mismatch assigning to '%s'",
+                       VarNode->Variable.Name);
+               return -2;
        }
+
+//     printf("Assign %p to '%s'\n", Value, var->Name);
+       SpiderScript_ReferenceValue(Value);
+       SpiderScript_DereferenceValue(var->Object);
+       var->Object = Value;
+       return 0;
+}
+
+/**
+ * \brief Get the value of a variable
+ */
+tSpiderValue *Variable_GetValue(tAST_BlockState *Block, tAST_Node *VarNode)
+{
+       tAST_Variable   *var = Variable_Lookup(Block, VarNode, 0);
        
+       if( !var )      return ERRPTR;
        
-       AST_RuntimeError(NULL, "Variable '%s' used undefined", Name);
-       
-       return ERRPTR;
+       SpiderScript_ReferenceValue(var->Object);
+       return var->Object;
 }
 
 /**
@@ -1368,22 +1368,33 @@ tSpiderValue *Variable_GetValue(tAST_BlockState *Block, const char *Name)
 void Variable_Destroy(tAST_Variable *Variable)
 {
 //     printf("Variable_Destroy: (%p'%s')\n", Variable, Variable->Name);
-       Object_Dereference(Variable->Object);
+       SpiderScript_DereferenceValue(Variable->Object);
        free(Variable);
 }
 
-void AST_RuntimeError(tAST_Node *Node, const char *Format, ...)
+void AST_RuntimeMessage(tAST_Node *Node, const char *Type, const char *Format, ...)
 {
        va_list args;
        
-       fprintf(stderr, "ERROR: ");
+       if(Node) {
+               fprintf(stderr, "%s:%i: ", Node->File, Node->Line);
+       }
+       fprintf(stderr, "%s: ", Type);
        va_start(args, Format);
        vfprintf(stderr, Format, args);
        va_end(args);
        fprintf(stderr, "\n");
+}
+void AST_RuntimeError(tAST_Node *Node, const char *Format, ...)
+{
+       va_list args;
        
-       if(Node)
-       {
-               fprintf(stderr, "   at %s:%i\n", Node->File, Node->Line);
+       if(Node) {
+               fprintf(stderr, "%s:%i: ", Node->File, Node->Line);
        }
+       fprintf(stderr, "error: ");
+       va_start(args, Format);
+       vfprintf(stderr, Format, args);
+       va_end(args);
+       fprintf(stderr, "\n");
 }

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