Changeset 6 for trunk/UBrainFuck.pas

Timestamp:

Feb 9, 2012, 3:22:38 PM (13 years ago)

Author:

chronos

Message:

• Modified: Interpretter now wait for key press if Read instruction is executed and no input character is available.
• Added: Actions to control program executions.

File:

• trunk/UBrainFuck.pas (modified) (4 diffs)

trunk/UBrainFuck.pas

@@ -18 +18 @@
   end;
 
+  TRunState = (rsStopped, rsPaused, rsRunning);
+
   { TBrainFuckInterpreter }
 
   TBrainFuckInterpreter = class
   private
+    FOnChangeState: TNotifyEvent;
+    FState: TRunState;
+    procedure SetState(AValue: TRunState);
     procedure Write(Value: Byte);
     function Read: Byte;
@@ -39 +44 @@
     procedure SingleStep;
     procedure Run;
+    procedure Pause;
+    procedure Stop;
     constructor Create;
     destructor Destroy; override;
+    property State: TRunState read FState;
+    property OnChangeState: TNotifyEvent read FOnChangeState write FOnChangeState;
   end;
 
@@ -58 +67 @@
 end;
 
+procedure TBrainFuckInterpreter.SetState(AValue: TRunState);
+begin
+  if FState = AValue then Exit;
+  FState := AValue;
+  if Assigned(FOnChangeState) then FOnChangeState(Self);
+end;
+
 function TBrainFuckInterpreter.Read: Byte;
 var
   Character: string;
 begin
-  if InputPosition < Length(Input) then begin
-    Character := Copy(Input, InputPosition, 1);
-    Result := Ord(Character[1]);
-    Inc(InputPosition);
-  end else
-    raise Exception.Create(SReadInputError);
+  while InputPosition >= Length(Input) do begin
+    Sleep(1);
+    Application.ProcessMessages;
+  end;
+  Character := Copy(Input, InputPosition, 1);
+  Result := Ord(Character[1]);
+  Inc(InputPosition);
 end;
 
@@ -140 +157 @@
 procedure TBrainFuckInterpreter.Run;
 begin
+  SetState(rsRunning);
   Reset;
   while SourcePosition < Length(Source) do begin
     SingleStep;
     Application.ProcessMessages;
-  end;
+    while State = rsPaused do begin
+      Sleep(1);
+      Application.ProcessMessages;
+    end;
+  end;
+  SetState(rsStopped);
+end;
+
+procedure TBrainFuckInterpreter.Pause;
+begin
+  if State = rsRunning then SetState(rsPaused);
+end;
+
+procedure TBrainFuckInterpreter.Stop;
+begin
+  SetState(rsStopped);
 end;