Fan.Sys.Err.doDumpStack C# (CSharp) Method

        static void doDumpStack(string msg, Exception err, int depth, StringWriter w)
        {
            // message
              for (int sp=0; sp<depth; sp++) w.Write(" ");
              if (!(err is Err.Val) && msg == err.Message) w.Write(err.GetType() + ": ");
              w.WriteLine(msg);

              // stack
              string stack = err.StackTrace;
              if (err is Err.Val)
              {
            Err e = ((Err.Val)err).err();
            if (e.m_stack != null) stack = e.m_stack;
              }
              if (stack != null)
              {
            string[] lines = stack.Split('\n');
            for (int i=0; i<lines.Length; i++)
            {
              // TODO - could be *way* more efficient

              string s = lines[i].Trim();
              int parOpen  = s.IndexOf('(');
              int parClose = s.IndexOf(')', parOpen);

              string source = s.Substring(parClose+1, s.Length-parClose-1);
              if (source == "") source = "Unknown Source";
              else
              {
            source = source.Substring(4);
            int index = source.LastIndexOf("\\");
            if (index != -1) source = source.Substring(index+1);
            index = source.LastIndexOf(":line");
            source = source.Substring(0, index+1) + source.Substring(index+6);
              }

              string target = s.Substring(0, parOpen);
              if (target.StartsWith("at Fan."))
              {
            int a = target.IndexOf(".", 7);
            int b = target.IndexOf(".", a+1);
            string pod  = target.Substring(7, a-7);
            string type = target.Substring(a+1, b-a-1);
            string meth = target.Substring(b+1);

            // check for closures
            int dollar1 = type.IndexOf('$');
            int dollar2 = dollar1 < 0 ? -1 : type.IndexOf('$', dollar1+1);
            if (dollar2 > 0)
            {
              // don't print callX for closures
              if (meth.StartsWith("call")) continue;
              // remap closure class back to original method
              if (meth.StartsWith("doCall"))
              {
                meth = type.Substring(dollar1+1, dollar2-dollar1-1);
                type = type.Substring(0, dollar1);
              }
            }

            target = FanStr.decapitalize(pod) + "::" + type + "." + meth;
              }

              for (int sp=0; sp<depth; sp++) w.Write(" ");
              w.Write("  ");
              w.Write(target);
              w.Write(" (");
              w.Write(source);
              w.Write(")");
              w.Write("\n");
            }
              }
              // inner exception
              Exception cause = err.InnerException;
              if (cause != null) doDumpStack(msg, cause, depth+1, w);
        }