Can't set BP in middle of line

[Michelle Long]

On Sunday, 4 November 2018 at 08:27:34 UTC, Rainer Schuetze wrote:
>
>
> On 03/11/2018 17:31, Michelle Long wrote:
>> On Saturday, 3 November 2018 at 08:10:37 UTC, Rainer Schuetze 
>> wrote:
>>>
>>>
>>> On 30/10/2018 16:21, Michelle Long wrote:
>>>> statement1; statement2;
>>>>
>>>> Would be nice to easily be able to set a BP just on 
>>>> statement2 without having to add a new line.
>>>>
>>>
>>> I haven't seen this with the VS native debugger and C++, so I 
>>> doubt it is feasible.
>> 
>> Supposedly it is possible. When you put a BP it has a "char" 
>> value which is usually set to 1. (you can see it in when you 
>> hover over the BP).
>> 
>> Supposedly setting the value to something else allows one to 
>> do BP's in the middle of lines. It may be only valid for 
>> certain languages though but it is doable in some cases as you 
>> can find information online about people doing it.
>> 
>> https://stackoverflow.com/questions/36166205/setting-a-breakpoint-in-the-middle-of-a-line-with-multiple-statements
>
> These examples are with the debugger for managed code (e.g. 
> C#), not the debug engine for native applications.
>
> I haven't yet seen any compiler (C++ or D) emit CodeView debug 
> information that contains more than the line number.


Is it then possible to simply split a line internally to handle 
it?

1. Surely the char/statement for the BP on a multi-statement line 
can be determined?

2. If such a BP exist then simply insert a new line in the text 
before compiling(I know it modifies the code but it's just 
whitespace and it could be an optional feature).

3. Then remove the inserted new line character after compiling. 
(might need to suppress file modifications temporarily).

4. When a BP is hit just re-calculate the line positions(will be 
offset by one and such.

Should be pretty simple to do and allows one to not have to worry 
about reformatting code just to add BP's.

I routinely do stuff like

if (x) return;

and I want a BP on the return, not the if. I have to insert the 
new line by hand just so I can add a BP!

Since this is a white space problem it really should be trival 
and technically should be supported by the compiler and 
debugger/IDE. It's a pretty basic problem and also helpful to 
have the ability to put BP's in the middle of lines.

It may actually be easier to implement though since the IDE 
already does have some of the capabilities.