Search in target is sometimes failing

Peter Goddard

@Ekopalypse Would you mind looking at my code for one part of my plugin that is failing?

Ekopalypse

Sorry, but there is a small, but unfortunately insurmountable problem,
I cannot program in C++, I am a python junkie :-)

Peter Goddard

@Ekopalypse No problem. Maybe you could just confirm that this is a memory issue for me? After restarting notepad my plugin seems to work and I can use it over and over again until it fails and then won’t work until I restart notepad. I’m pretty sure this means it’s a memory problem, and I don’t really know where to go from here

Ekopalypse

@Peter-Goddard

until it fails and then won’t work until I restart notepad

yes, that could mean that you have an overflow.
There are several ways to find out what is causing it.
Old school, use print statements in your code and check certain parameters.
More modern, use Visual Studios features like Analyzer and Debugger to see what is going on.
I assume you are using Visual Studio for development,
there is one setting I would suggest to activate, it is to treat every warning as an error.
(Project->Properties->Configuration Properties->C/C+±>General->Treat warnings as errors->Yes)

Peter Goddard

@Ekopalypse

Thanks, I’ll try that.

There is another thing I have noticed and I wonder if you could help me with it. The text file I am working on is around 40’000 lines long, and as I said before I am formatting small parts of that file and eventually it will start to mess up. What I have noticed though, is that when I copy and paste a part of the original text file to a separate notepad tab and try to format it, then once it’s formatted it, delete it and then repeat the process, the formatting process never messes up. Could it be that the length of the text file has something to do with how many times I can use my plugin on it?

Ekopalypse

@Peter-Goddard

yes, could be but to me it sounds more like an issue with the “new” content.
For example, let’s say we have a text like this

This is a sampl of a text which has two wrong words named sampl.

Now let’s assume your plugin is used to auto correct wrong words.
If your code logic would be

find all instances of the wrong word
Loop over the results and replace with the correct word

then it would fail as you invalidate the position of the second sampl
word by replacing the first one.
In such a scenario replacing from bottom to top would avoid this.
Of course, there are multiple other ways to solve this issue as well.

Peter Goddard

@Ekopalypse

I see what you mean, but I don’t think that applies to my situation as when my plugin fails, I can simply reopen notepad and continue to format some more content until it fails again. If this issue was happening to every instance of content all of the time then I could see why this makes sense.

Ekopalypse

@Peter-Goddard

yes, it could be that this is not the issue, but a new npp start also means that your data is not the same as before,
but you certainly have more information to evaluate this than I do,
I am fishing here more or less in the dark.
Can you describe in pseudocode what you are doing, maybe this could be helpful to find the issue.

Peter Goddard

@Ekopalypse

Sure. This plugin just places a “\n” infront every case of “<” in the selected area.

function(){

Set the target search area to the area that has been selected.

Look for the first case of “<” in the targeted area.

While a, “<” can be found, get the placement of, “<”, insert a “\n” at that spot. Set the beginning of the target search area just ahead of where “<” is now found and increase the end of the target search area by 1. Search again for the next “<” in the target search area

}

Ekopalypse

@Peter-Goddard

From your explanation this doesn’t work.
You need to advance the start by 2, correct?
Assuming the following, 0123… are positions made visible.

0123456789
ab<def<h

position of < is 2 correct?
Insert c at that position results in

0123456789
abc<def<h

and if you set the start now to position+1 (=3) it will re-find the same <

Sure this is what you do?
My pseudocode would look like this

target = selected text
target_end = last position of selected text
position = search in target for '<'
while position > -1:
    insert char '\n' at position 
    reset target_start to position+2 and target_end to target_end+1
    position = search in target for '<'

Peter Goddard

@Ekopalypse

Sorry, I am increasing the start by 2, I just didn’t clarify that. I meant that when I said, “Set the beginning of the target search area just ahead of where “<” is now found”. My mistake. I know my code works because when I select the text,

<<<<

it results in

<
<
<
<

Sorry for the confusion

Peter Goddard

@Ekopalypse Of course, my code works, until it breaks liked we talked about before

Ekopalypse

@Peter-Goddard

ok, then I would say it is time to debug/print some info about
target_start, target_end and position found.
Make a debug build, use OutputDebugStringW and tools like DebugView
to capture the output. Of course only, if you can’t run within Visual Studio.

Ekopalypse

Actually, it doesn’t have to be a debug build, a release build should do it as well.

Peter Goddard

@Ekopalypse

Okay, I’m trying that now. I am using visual studios and I have added in my code a OutputDebugStringW, now where would I find the values that it outputs when I use my plugin in notepad?

Ekopalypse

@Peter-Goddard

Did you start npp from within Visual Studio or did you attach (from Debug menu) npp to visual studio? If so, those should appear in
View->Output window.

Peter Goddard

@Ekopalypse

I think I have made a very obvious mistake. I forgot to specify my search flag as you mentioned in my other post. After switching it to Regexp, it seems to be working. I feel like that was very obvious and you have taken a lot of your time to help me, so thank you again for all your help.

If anything else happens, I’ll post again. Thanks.