macro_rules! declare_invocable_impl {
{
// These arguments are used to fill in some blanks that we need to use
// when handling an update sink.
$( update_gen: $update_gen:ident,
update_arg: { $sink:ident: $update_arg:ty } ,
update_arg_where: { $($update_arg_where:tt)+ } ,
sink_fn: $sink_fn:expr
)?
} => { ... };
}
Expand description
Helper: Declare a blanket implementation for Invocable.
We provide two blanket implementations: Once over a fn() taking an update sink, and once over a fn() not taking an update sink.