syntax_data: {"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// to the bound variable's index from the binder from which it was instantiated),
context_before:     /// where `N` is the placeholder variable's anonymous index (which corresponds
context_after:     /// and `U` is the universe index in which it is instantiated, or totally omitted