# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1209169904 -7200
# Node ID 4b3cde1edd1994ad1e761fb9844ca338c5eaef4e
# Parent  5a13e435dd0ed25c5b148b7d96a10d347a65a721
Make the last operation None if no operations have yet been generated.
Made previous ImmediateInstruction subclasses employ AddressInstruction instead.
Introduced ImmediateInstruction for *Index classes.
Fixed exception handling for keyword arguments.

diff -r 5a13e435dd0e -r 4b3cde1edd19 micropython/ast.py
--- a/micropython/ast.py	Mon Apr 21 00:35:18 2008 +0200
+++ b/micropython/ast.py	Sat Apr 26 02:31:44 2008 +0200
@@ -194,7 +194,10 @@
 
         "Return the last added instruction."
 
-        return self.code[-1]
+        try:
+            return self.code[-1]
+        except IndexError:
+            return None
 
     # Internal helper methods.
 
@@ -340,7 +343,7 @@
                     # Add space for arguments appearing before this one.
 
                     if frame_pos < pos:
-                        self.new_op(ReserveFrame(pos - frame_pos)
+                        self.new_op(ReserveFrame(pos - frame_pos))
 
                     # Generate code for the keyword and the positioning
                     # operation.
@@ -367,7 +370,7 @@
                     # Where no position is found, this could be an extra keyword
                     # argument.
 
-                    except ValueError:
+                    except self.paramtable.TableError:
                         extra_keywords.append(arg)
                         continue
 
diff -r 5a13e435dd0e -r 4b3cde1edd19 micropython/rsvp.py
--- a/micropython/rsvp.py	Mon Apr 21 00:35:18 2008 +0200
+++ b/micropython/rsvp.py	Sat Apr 26 02:31:44 2008 +0200
@@ -67,18 +67,27 @@
 
 AR = AddressRelativeInstruction
 
-class ImmediateInstruction(Instruction):
+class AddressInstruction(Instruction):
 
     "An instruction loading an address directly."
 
     def __repr__(self):
         return "%s(%r)" % (self.__class__.__name__, self.attr.location)
 
+Address = AddressInstruction
+
+class ImmediateInstruction(Instruction):
+
+    "An instruction employing a constant."
+
+    def __repr__(self):
+        return "%s(%r)" % (self.__class__.__name__, self.attr)
+
 Immediate = ImmediateInstruction
 
 # Instructions operating on the value stack.
 
-class LoadConst(Immediate):         "Load the constant from the specified location."
+class LoadConst(Address):           "Load the constant from the specified location."
 class Duplicate(Instruction):       "Duplicate the top of stack."
 class Pop(Instruction):             "Pop the top of stack."