gistfile1.txt

public override object Visit (Constant constant)
			{
				if (constant.GetValue () == null) 
					return new NullReferenceExpression (Convert (constant.Location));
				string literalValue;
				if (constant is ILiteralConstant) {
					literalValue = new string (((ILiteralConstant)constant).ParsedValue);
				} else {
					literalValue = constant.GetValueAsLiteral ();
				}
				object val = constant.GetValue ();
				if (val is bool)
					literalValue = (bool)val ? "true" : "false";
				var result = new PrimitiveExpression (val, Convert (constant.Location), literalValue);
				return result;
			}