Why? Seems to me that it's precisely equivalent to Golang's error handling story (assuming you mean something like Result). In fact, it's a lot easier to handle errors individually that way, both because it tends to make it harder to use a return value without checking for errors and because its generic nature means that you can handle different errors differently without having to deal with interfaces.
If you mean that it's more typing to write "return err" and it forces you to think about it more, I don't really buy that. "return err" is 10 characters; "map" (e.g. in Haskell) is 3 and "try!()" is 6. I really doubt that the difference between 3 and 10 characters has any practical outcome. For Golang programmers, "return err" is muscle memory.
I should have said the monadic form of Option<>. When you use it monadically, the result is nearly equivalent to exception handling; you call a function and the default behavior is to bundle up the error and just throw it up. It is true that if you are manually unwrapping it every single time, it's equivalent to checking every time.
"For Golang programmers, "return err" is muscle memory."
First, as I said, no, I actually think about it every time. And second, I bet you end up with "muscle memory" default handling under any scheme (for instance, exceptions: don't catch them or rethrow them)... in the end, you can bring the horse to water but you can't make it drink. You can only feel good that at least you brought it and you did your part. Option<>, even manually unwrapped, does not force the programmer to do something sensible with the error any more than any thing else does, or indeed, can.
Why? Seems to me that it's precisely equivalent to Golang's error handling story (assuming you mean something like Result). In fact, it's a lot easier to handle errors individually that way, both because it tends to make it harder to use a return value without checking for errors and because its generic nature means that you can handle different errors differently without having to deal with interfaces.
If you mean that it's more typing to write "return err" and it forces you to think about it more, I don't really buy that. "return err" is 10 characters; "map" (e.g. in Haskell) is 3 and "try!()" is 6. I really doubt that the difference between 3 and 10 characters has any practical outcome. For Golang programmers, "return err" is muscle memory.