it appears that the return type from
create_static still captures the lifetime of its argument
_s, despite being declared as
+ 'static, and that argument not being used. Which seems odd, especially since if you replace
&str in args of both
create_static, it works fine (the return type doesn't capture the unnamed lifetime of &str).
What am I missing here, and/or is there a way to use
impl Trait in the return position to indicate that the returned impl is