syntax_data: {"ast_node_type":"variable","tokens":[{"end":82,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                         let node_args = self.typeck_results.node_args(fun.hir_id);
context_before:                     if let Some((adt_def, index)) = adt_data {
context_after:                         let user_provided_types = self.typeck_results.user_provided_types();