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Comment by imedadel | Hacker News Reader

I think typing isn't my issue (so far), but rather the performance. On one hand, it's one less thing to think about while figuring out a problem, but on the other hand, it might reduce the performance of my solution, and in that case, going back and refactoring the code to use the correct types would be a waste of time...

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You seem to have a misconception of what `auto` entails... It just means "deduce type from the right-hand side of the assignment statement", instead of having to type it explicitly. Doesn't make your program dynamically typed or runtime typed all of a sudden.

Oh interesting. Why do you think auto would affect run-time performance? Could you describe an example?

I think auto won't have any run-time performance since type deduction happens at compile-time.

Also read this https://stackoverflow.com/questions/19618759/c-11-auto-compi...

I'm already well aware of this. I'm asking why the OP thinks otherwise. It's not outright impossible to make it affect performance [1] but I'm trying to see what the concern is.

[1] Like by taking the approach that results in a cast, e.g. here: https://news.ycombinator.com/item?id=20493263

Oh, I see. I didn't know that type deduction happens at compile-time :o

Yeah, that's how type systems work in most languages. That's why we have them: they prevent mistakes before you even run your code :)

Why would you think that using auto would reduce the performance of your code?

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