uuid.MustParse should panic error in error type

[viuts]

Currently MustParse panic the error in string type,

panic should be an error type, so the recover can have consistance use of err.Error()

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[viuts]

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[pborman]

Normally MustParse is only used when initializing global variables (or init functions). Any place else should probably be done with Parse and then check the error. I don't disagree that panicking with an error is perhaps slightly better. My only question is if it is worth enough to change the API.

[viuts]

@pborman I know that golang does not encourage using defer-catch to throw errors, but after suffering from all of those if err != nil, We decided to use defer-catch patterns to handle errors, especially we are using grpc. we do expect the value from recover being an error, consider the follow code.

func Catch(err *error) {
    if r := recover(); r != nil {
        panicError := r.(error)
        *err = panicError
    }
}

if the library panicking with a string, this code will get crash again when type assertion, it will be better if the library can follow the common practice which is panicking an error.

of course we can always check when type assertion

func Catch(err *error) {
    if r := recover(); r != nil {
        panicError, ok := r.(error)
        if !ok {
            panicError = fmt.Errorf("%v", r)
        }
        *err = panicError
    }
}

but it feels slightly redundant if user need to do it manually

[noahdietz]

Hello. I agree with @pborman that changing the value passed to panic now would be backwards incompatible to existing uses of recover catching this panic. There is no requirement that the panic be given an error, a string is allowed. So for these reasons, I will close this. Thanks for the consideration.