> Date: Fri, 17 Jan 2025 20:39:57 +0100
> From: Paolo Bonzini
> Subject: [PATCH 04/10] rust: callbacks: allow passing optional callbacks as
> ()
> X-Mailer: git-send-email 2.47.1
>
> In some cases, callbacks are optional. Using "Some(function)" and "None
In some cases, callbacks are optional. Using "Some(function)" and "None"
does not work well, because when someone writes "None" the compiler does
not know what to use for "F" in "Option".
Therefore, adopt () to mean a "null" callback. It is possible to enforce
that a callback is valid by adding
