Better debugging with aspect generated code

Elements Oxygene
1

When you have an assembly aspect that changes the code of a method, and this code fails (or shows a failed assert), the debugger shows the aspect as current code line.

Example source code:

[assembly: MyAspect]

method MyMethod;
begin
    //some code
end;

The aspect MyAspect changes the code of MyMethod to:

method MyMethod;
begin
    System.Diagnostics.Debug.Assert(false, 'the error'); //inserted by the aspect, not in the source code
    //some code
end;

When MyMethod is executed, the assert is shown, but the debugger breaks on the line:

[assembly: MyAspect]

instead of (what should be more logical for debugging) on the line

method MyMethod;

Is it possible to change this behavior?

2

Wouldn’t that be even more confusing though?

3

No, less - it should stop in the code is executed, not where the code generation is executed

4

Right, but the line its stopping at doesn’t exist in that code…

5

So then better stop in a complete other unit?
Instead of as close as possible to the real problem line?

6

im just putting the thought out.

if I had

method MyMethod;
begin
    writeLn("Hello").
end;

and it would break on the writeLn with “the error”, I’d be confused AF.

7

But it confuses me when the code breaks on the [assembly:MyAspect] line in assembly.pas, while the call stack window says that the code is in mycode.pas, and when I doubleclick on the line in the call stack window, it goes to assembly.pas instead of mycode.pas - while it is stating that the error occurred in mycode.pas, method myMethod.

8

There are four possibilities:

  1. I added code before the original body -> this should stop on the begin statement of the body
  2. I added code after the original body -> this should stop on the end statement of the body
  3. I replaced the complete body -> this should stop on the begin statement of the body
  4. I added a complete new method -> this can stop on the aspect line as there is no method in the source
9

But not important enough to waste your time on today.
Have a nice evening tonight and a good flight tomorrow!

We talk about this later :smile:

10

In the end int comes down to what Carlo thinks about this; I don’t feel strongly. I just wanted to make the point that it’s not clear-cut :wink:

thanx! see you when I get back!