Allow variables declared in do-while loop body to be in scope in the condition?

[Tagir Valeev]

Note that this is not the compatible change, as the variable may shadow
same-named field which was in the scope of condition before.

On Mon, Jan 15, 2024, 08:49 David Alayachew <davidalayachew at gmail.com>
wrote:

> Hello Amber Dev Team,
>
> Would it make sense and would there be value in allowing variables
> declared in the body of a do-while loop to still be considered in scope for
> the condition of the same do-while loop?
>
> Basically, the following example is currently not valid Java, but should
> it be?
>
> ```java
>
> do
> {
>
>    final var someVar = someMethod();
>
>    doSomethingWith(someVar);
>
>    //etc.
>
> }
>
> while (someVar.someBooleanReturningMethod());
>
> ```
>
> I think this is clear, simple, and is better than the alternative.
>
> ```java
>
> /* Must be mutable! :( */
> /* And you probably need a default value too! */
> var someVar = someYuckyDefaultOrWorseYetNull;
>
> do
> {
>
>    //code
>
> }
>
> while (someVar != 42);
>
> //And annoyingly enough, the variable is still in scope outside of the
> loop! Blegh.
>
> ```
>
> Since do-while loops are very old, I wouldn't be surprised if someone else
> has asked this before. But regardless, I couldn't find anything, so I ask
> now -- is there any value in doing this?
>
> Thank you for your time and help!
> David Alayachew
>
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