Well, there are many legitimate cases for using the equality operator. Insisting someone is doing something wrong is downright wrong and you shouldn't be teaching floating-point numbers.
A few use cases are: Floating-points differing from default or initial values and carrying meaning, e.g. 0 or 1 translates to omitting entire operations. Then there is also the case for measuring the tinyest possible variation when using relative tolerances are not what you want. Not exhaustive.
If you use == with fp, it only means you should've thought about it thoroughly.
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Well, there are many legitimate cases for using the equality operator. Insisting someone is doing something wrong is downright wrong and you shouldn't be teaching floating-point numbers. A few use cases are: Floating-points differing from default or initial values and carrying meaning, e.g. 0 or 1 translates to omitting entire operations. Then there is also the case for measuring the tinyest possible variation when using relative tolerances are not what you want. Not exhaustive. If you use == with fp, it only means you should've thought about it thoroughly.