Code cleanup

Axiom/Axiom.Core/Interpreter/Emitter.cs

@@ -14,6 +14,7 @@ namespace Axiom.Interpreter
     private BinaryWriter outputStream;    // the assigned output stream
     private BinaryWriter activeStream;    // the active stream
     private Stack<BinaryWriter> writeStack = new Stack<BinaryWriter>();
+    private Stack<CapturedCode> captureStack = new Stack<CapturedCode>();
     private bool isCapturing = false;
     private bool debug = true;
 
@@ -37,7 +38,7 @@ namespace Axiom.Interpreter
         isCapturing = true;
     }
 
-    public CapturedCode EndCapture()
+    public void EndCapture()
     {
         if (!isCapturing)throw new InvalidOperationException("EndCapture called without a matching BeginCapture.");
         activeStream.Flush();
@@ -47,11 +48,16 @@ namespace Axiom.Interpreter
         activeStream.Dispose();       
         activeStream = writeStack.Pop();
         isCapturing = writeStack.Count > 0;
-        return new CapturedCode(capturedBytes);
+        captureStack.Push(new CapturedCode(capturedBytes));
     }
 
-    public void Emit(CapturedCode code)
+    /// <summary>
+    /// EmitCapture - Later, for CONTINUE semantics, we can Peek() at the top of the captureStack to get the increment code without popping it.
+    /// </summary>
+    public void EmitCapture()
     {
+      if(0==captureStack.Count)throw new InvalidOperationException("The CaptureList is empty.");
+      CapturedCode code = captureStack.Pop();
       activeStream.Write(code.Bytes,0,code.Length);
     }
 

Axiom/Axiom.Core/Interpreter/Parser.cs

@@ -246,11 +246,11 @@ namespace Axiom.Interpreter
       DoForCondition(); // e.g., I < 10                     // emit the for condition
       codePointerFalseBranch = CodePointer();               // get the location in the stream for the defaddr2 that follows
       Emit(Parser.ParserSymbols.defaddr2, 0L);              // emit defaddr2 (jump if false) with dummy address of 0L
-      BeginCapture();                                       // start a new code emit frame
+      BeginCapture();                                       // start a new code emit frame.  This is how we implement deferred emit
       DoForIncrement();                                     // emit the increment code e.g., I = I + 1
-      CapturedCode code = EndCapture();                           // end the capture and retrieve the emitted code
+      EndCapture();                                         // end the capture 
       DoForBlock();                                         // emit the BODY
-      Emit(code);                                           // emit the increment
+      EmitCapture();                                        // emit the increment code we capture between BeginCapture and EndCapture
       if (IsInError) { loopStack.Pop(); return; }           // check error condition
       Emit(Parser.ParserSymbols.goto2, codePointerL1);      // jump back to condition after the body
       codePointerL2 = CodePointer();                        // get the location in the stream for the L2 exit location