pub fn select_from_hierarchy<'a, 'b, Key>(
root_node: &'a DiagnosticsHierarchy<Key>,
selector: &'b Selector,
) -> Result<SelectResult<'a, Key>, Error>
pub fn select_from_hierarchy<'a, 'b, Key>(
root_node: &'a DiagnosticsHierarchy<Key>,
selector: &'b Selector,
) -> Result<SelectResult<'a, Key>, Error>