#220 : Bug - Inconsistant line step / breakpoint response

Given the following program:

 4 Method Main()
 5    Define A As Integer
 6    For A = 1 To 3
 7       Trace("" + A)
 8    Next
 9 End Method

Putting a breakpoint on line 7 will cause the program to go into debug mode for each iteration of the loop. In other words, to get through the program, you have to hit the run button 4 times before the program stops running. That acts as expected. Putting a breakpoint on line 6 however, only breaks into debug mode for the first iteration through the loop. In other words, to get through the program, you have to hit the run button 2 times before the program stops running.

In short, while stepping through the code, the entire loop (lines 6, 7, and 8) gets repeated, but putting a breakpoint on line 6 only gets honored once.

This also happens with whiles.

I agree that seems illogical... even more so for a 'while' loop where the condition is clearly on the 1st line of the loop. I'm also pretty sure that Visual Studio doesn't work this way. I'm going to guess that its the way Phrogram generates the .Net code underneath. Your computer isn't really running Phrogram code. Its running IL (Yes I know its really running x86 but for the purpose of the .Net debugger its not). Each IL statement gets tagged back to the 'original' line of source code so we know when to breakpoint and error etc. So I'm betting the IL for the 'for' line is actually only run once.. and the loop consists of the inner code and the 'next'. I shall investigate and I think the right thing to do is match visual studios behaviour.

If that were the case, that the For line is executed only once, shouldn't stepping through the code only hit the for line once? As I indicated, stepping through the code correctly hits all the lines, including the For line, which is why the breakpoint response seems inappropreate.

Sorry I missed that part of your post... yes it does make it seem even more wrong.. I'll be sure to update it when I find the issue.