[alkonaut]

I have a linter in my code that shouts at me if I use exact equality for floats.

But I regret not making an exception for the constant zero, because it's one of the cases where you probably should accept it. I.e. if (f != 0.0) {...}

[vikingerik]

Zero shouldn't be an exception there. If f had been set from something like f = a - b, then you're in the same situation where f might be almost but not exactly zero.

The linter wouldn't know where f came from, so it should flag all floating point equality cases, and have some way that you can annotate it for "yeah this one is okay."

[alkonaut]

The thing is that

if (f == 0.0) means "is f exactly zero so it's not initialized" 99 times for every one time it means "is f zero-ish because of a cancellation/degeneracy/whatever"

I just found that I have now annotated it for "yeah this one is ok" about 100 times, and caught zero cases where I meant to do a comparison to zero-or-very-nearly-so but accidentally wrote == 0.0.

So my conclusion is: I would have had less noise in my code with that exception in the linter, and the linter had been equally useful.

[1718627440]

The idea is not to do it with values derived from arithmetic, but e.g. from measurements where a real zero is very unlikely and indicates something different.

[vikingerik]

Right, but that's not something a linter could know.