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yoyohello13 2 hours ago

What? Results have a limited number of possible error states that are well defined.

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Dylan16807 2 hours ago | parent [-]

Some call points to a function that returns a Result will never return an Error.

Some call points to a function that returns an int will never return -2.

Sometimes you know things the type system does not know.

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Rohansi 2 hours ago | parent [-]

The difference is functions which return Result have explicitly chosen to return a Result because they can fail. Sure, it might not fail in the current implementation and/or configuration, but that could change later and you might not know until it causes problems. The type system is there to help you - why ignore it?

	▲	Dylan16807 2 hours ago \| parent [-]
		Because it would be a huge hassle to go into that library and write an alternate version that doesn't return a Result. So you're stuck with the type system being wrong in some way. You can add error-handling code upfront but it will be dead code at that point in time, which is also not good.