syntax_data: {"ast_node_type":"variable","tokens":[{"end":69,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let async_drop_trait = self.lang_items().async_drop_trait()?;
context_before:     ) -> Option<ty::AsyncDestructor> {
context_after:         self.ensure_ok().coherent_trait(async_drop_trait).ok()?;