[apple1417]

Having run into similar problems several times, I've also never really been satisfied with the solutions. You have to have different types to cause compile errors, but then you have throw those types away whenever you perform any actual operations on them.

    struct TypeA { int inner; };
    struct TypeB { int inner; };

    struct TypeA a1, a2;
    // whoops
    TypeB result = {.inner = a1.inner + a2.inner};

Don't get me wrong, where I've used this sort of pattern it's definitely caught issues, and it definitely massively lowers the surface area for this type of bug. But I still feel like it's quite fragile.

The use case I felt worked best was seperating out UTC datetime vs localised datetime structs - mainly since it's something you already had to use function calls to add/subtract from, you couldn't play with raw values.