syntax_data: {"ast_node_type":"variable","tokens":[{"end":56,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let mut user_ty = *user_provided_types.get(hir_id)?;
context_before:     let user_provided_types = typeck_results.user_provided_types();
context_after:     debug!("user_subts_applied_to_ty_of_hir_id: user_ty={:?}", user_ty);