syntax_data: {"ast_node_type":"variable","tokens":[{"end":84,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let option_did = tcx.require_lang_item(LangItem::Option, body.span);
context_before:                 // Compute Option<yield_ty>
context_after:                 let option_adt_ref = tcx.adt_def(option_did);