pub trait LayerExt {
// Provided methods
fn method(
self,
method: Method
) -> FilterLayer<Box<dyn Fn(&mut HttpContext, &Request) -> Result<(), StatusCode>>>
where Self: Sized { ... }
fn filter<F>(self, f: F) -> FilterLayer<F>
where Self: Sized,
F: Fn(&mut HttpContext, &Request) -> Result<(), StatusCode> { ... }
}