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by sdegutis 2541 days ago
To be honest, I don't remember exactly what feature it was. Just that I couldn't easily encapsulate a 2d grid of "replaceable" cells. This was like 4-5 months ago and the only documentation we had on C++ at the time was the official Stroustrup book, which was dense.
1 comments
Const-me 2541 days ago
The problem with C++ isn’t the lack of documentation, it’s too much documentation, which often contradicts one another, or just wrong.

For 2D grid, here’s a code that I usually write when I need one, untested: https://gist.github.com/Const-me/7aee0ef4087d250cc9b82463988...

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sdegutis 2541 days ago
That sums up my experience. It's hard to find good quality docs, that's up-to-date and not just a beginner's intro that doesn't answer my questions. The only other alternative usually seems to end up being man-pages or other extremely dense and legalesque docs like a ISO standard or something.

Thanks for the sample grid, I've bookmarked it, this'll be helpful for me and my son to understand where we took the wrong road in our implementation.

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Const-me 2541 days ago
Couple interesting points.

1. const correctness is awesome. I miss it so much in C# which I happen to code a lot as well. When you have a function which accepts `const Grid<int>& grid`, you can’t call resize() nor change cell values. If you’ll try, the code won’t compile. My given name is Const so I have bias, but still.

2. asserts. They aren’t even C++, these are from C, but IMO they have better ergonomics than C++ exceptions. They compile into nothing in release builds i.e. don’t affect performance, but in debug builds they trap to debugger right away, showing what exactly is not OK. For production code, sometimes it’s a good idea to use preprocessor trickery to turn failed asserts into scary log messages, in release builds.

P.S. It’s possible to implement much better resize(). When neither old nor new size is empty, the version on that gist will essentially turn old data into garbage. A better solution for that case, make a new vector on the stack, write a loop to crop or expand the items (e.g. calling std::copy_n), then call vector::swap to replace Grid::data vector with the newly built one.

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