Error returns and checked exceptions are isomorphic. There's nothing you can do with one that you can't do with the other. But I agree with the underlying poi

Error returns and checked exceptions are isomorphic. There's nothing you can do with one that you can't do with the other. But I agree with the underlying point you're making. The error mechanism that a language provides determines how a programmer will think about handling errors. Exceptions make you think about error handling as control flow. Error returns make you think about error handling as unwrapping data.