syntax_data: {"ast_node_type":"variable","tokens":[{"end":29,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let span = self.span;
context_before:     fn valtree_to_pat(&self, cv: ValTree<'tcx>, ty: Ty<'tcx>) -> Box<Pat<'tcx>> {
context_after:         let tcx = self.tcx;