I'm looking for a way to do the following:
fn get_foo(&self, some_param: &str) -> BoxStream<'_, Foo> {
let some_other_param = get_other_param();
query!(
r#"
SELECT * FROM "foo"
WHERE
"foo" = $1
AND "bar" = $2
"#,
some_param,
&some_other_param
)
.fetch_many(&self.db)
.map(row_to_foo)
.map(do_something_else)
.filter(whatever)
.boxed()
}
The issue is that the stream created by fetch_many holds a reference to pretty much everything it needs. Creating ad-hoc futures is supported by the language, so whenever this happens I can just do:
fn get_foo(&self) -> BoxFuture<'_, Vec<Foo>> {
async move {
// Clone/capture whatever is needed.
// ...
}.boxed()
}
I'm looking for something similar for streams in stable Rust without having to implement a custom self-referential stream type, or alternatively some library that does the boilerplate for such wrapper types.