expression type A is a subtype of pattern type B diagnostics

[Archie Cobbs]

On Tue, Apr 1, 2025 at 11:49 AM Liam Miller-Cushon <cushon at google.com>
wrote:

> So all of this seems deliberate and working as intended, I was just
> curious what the rationale for the change was. Does anyone remember the
> history or have pointers to discussions about it on list?
>

I don't know what the stated rationale was at the time, but the change
makes intuitive sense to me now: Why should "e instanceof Y x" generate an
error when "e instanceof Y" does not? That is to say: the correctness of
the type test itself, which is what the error is about, has nothing to do
with whether or not you happen to be declaring a new variable that captures
a successful outcome of that test.

-Archie

-- 
Archie L. Cobbs
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