Removed block instance variables from language, and slightly optimized the...

Removed block instance variables from language, and slightly optimized the evaluation primitive handling
Signed-off-by: Stefan Marr <git@stefan-marr.de>

core-lib @ 52591c6d

-Subproject commit 692cfb135a04b47a2393cbae7c7b72f4d8c0869e
+Subproject commit 52591c6d7c559f3bd4d783ba81c6e63181b9ac39

src/som/vmobjects/block.py

@@ -3,51 +3,32 @@ from som.vmobjects.primitive import Primitive
 
 class Block(Object):
     
-    METHOD_INDEX           = Object.NUMBER_OF_OBJECT_FIELDS
-    CONTEXT_INDEX          = 1 + METHOD_INDEX
-    NUMBER_OF_BLOCK_FIELDS = 1 + CONTEXT_INDEX
+    NUMBER_OF_BLOCK_FIELDS = Object.NUMBER_OF_OBJECT_FIELDS
+    
+    _immutable_fields_ = ["_method", "_context"]
     
     def __init__(self, nilObject, method, context):
         Object.__init__(self, nilObject)
         self._number_of_arguments = 0
-        self._set_method(method)
-        self._set_context(context)
+        self._method  = method
+        self._context = context
         
     def get_method(self):
         # Get the method of this block by reading the field with method index
-        return self.get_field(self.METHOD_INDEX)
-  
-    def _set_method(self, value):
-        # Set the method of this block by writing to the field with method index
-        self.set_field(self.METHOD_INDEX, value)
-  
+        return self._method
+    
     def get_context(self):
         # Get the context of this block by reading the field with context index
-        return self.get_field(self.CONTEXT_INDEX)
-
-    def _set_context(self, value):
-        # Set the context of this block by writing to the field with context index
-        return self.set_field(self.CONTEXT_INDEX, value)
+        return self._context
 
     def _get_default_number_of_fields(self):
         # Return the default number of fields for a block
         return self.NUMBER_OF_BLOCK_FIELDS
   
     class Evaluation(Primitive):
-        def __init__(self, num_args, universe):            
-            def _invoke(ivkbl, frame, interpreter):
-                # Get the block (the receiver) from the stack
-                rcvr = frame.get_stack_element(ivkbl._number_of_arguments - 1)
-    
-                # Get the context of the block...
-                context = rcvr.get_context()
-    
-                # Push a new frame and set its context to be the one specified in
-                # the block
-                new_frame = interpreter.push_new_frame(rcvr.get_method(), context)
-                new_frame.copy_arguments_from(frame)
-            
-            Primitive.__init__(self, self._compute_signature_string(num_args), universe, _invoke)
+        def __init__(self, num_args, universe, invoke):
+            Primitive.__init__(self, self._compute_signature_string(num_args),
+                               universe, invoke)
             self._number_of_arguments = num_args
 
         def _compute_signature_string(self, num_args):
@@ -55,13 +36,25 @@ class Block(Object):
             signature_string = "value"
             if num_args > 1:
                 signature_string += ":"
-
-            # Add extra value: selector elements if necessary
-            for _ in range(2, num_args):
-                signature_string += "with:"
+                if num_args > 2:
+                    # Add extra with: selector elements if necessary
+                    signature_string += "with:" * (num_args - 2)
           
             # Return the signature string
             return signature_string
 
 def block_evaluation_primitive(num_args, universe):
-    return Block.Evaluation(num_args, universe)
+    return Block.Evaluation(num_args, universe, _invoke)
+
+def _invoke(ivkbl, frame, interpreter):
+    # Get the block (the receiver) from the stack
+    assert isinstance(ivkbl, Block.Evaluation)
+    rcvr = frame.get_stack_element(ivkbl._number_of_arguments - 1)
+
+    # Get the context of the block...
+    context = rcvr.get_context()
+
+    # Push a new frame and set its context to be the one specified in
+    # the block
+    new_frame = interpreter.push_new_frame(rcvr.get_method(), context)
+    new_frame.copy_arguments_from(frame)