syntax_data: {"ast_node_type":"variable","tokens":[{"end":33,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let parts = self.split();
context_before:     pub fn sig(self) -> GenSig<I> {
context_after:         GenSig { resume_ty: parts.resume_ty, yield_ty: parts.yield_ty, return_ty: parts.return_ty }