syntax_data: {"ast_node_type":"other","tokens":[{"end":54,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // the compiler do a bunch of work needlessly.
context_before:         // the nominal obligations of `Sized` would in-effect just elaborate `MetaSized` and make
context_after:         if self.tcx().is_lang_item(def_id, LangItem::Sized) {