Question about Pattern-Matching for Switch

[David Alayachew]

Makes sense, ty vm. If that is the justification, I am ok with it. I would
prefer a more clear error though.

On Sun, Jun 2, 2024 at 3:57 AM Olexandr Rotan <rotanolexandr842 at gmail.com>
wrote:

> Hi David! I`ve looked into compiler sources a bit, and this error is
> reported in Attr class when attributing switch expressions.Basically,
> compiler does not know which type to assign to switch expression, as there
> is not case return types, you could think of it as switch expression of
> "void" type, so it cant be nor assigned nor returned, so compiler treats it
> like an error. Its not a pattern matching thing, just general
> switch behaviour
>
> On Sun, Jun 2, 2024 at 5:58 AM David Alayachew <davidalayachew at gmail.com>
> wrote:
>
>> Hello Amber Dev,
>>
>> Apologies for not having tested many features lately for this project
>> (and others). Juggling insane workloads at work.
>>
>> Today is the first day I had a moment to breath in months, so I tried out
>> some stuff, and I was confused.
>>
>> I have a Switch Expression where the input is a Sealed Type. For this
>> particular Switch Expression, almost every branch of it is going to throw
>> an Exception of some sort. I added all of the failure cases to the Switch
>> Expression, pressed compile, and it threw the following compilation error.
>>
>> > InputFormat.java:161: error: switch expression does not have any result
>> expressions
>> >                   switch (next)
>>
>> Again, there is going to be one result expression, so I am not blocked by
>> this compilation error.
>>
>> I was just really surprised to see an intentional road block there.
>>
>> Why is there a compilation error if all of the arms of a Switch
>> Expression are just throwing Exceptions?
>>
>> Thank you for your time and help!
>> David Alayachew
>>
>
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