syntax_data: {"ast_node_type":"variable","tokens":[{"end":64,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:     if let Some(fn_decl) = tcx.hir_fn_decl_by_hir_id(owner_id) {
context_before:     let owner_id = tcx.local_def_id_to_hir_id(owner_def);
context_after:         let closure_env_param = cx.closure_env_param(owner_def, owner_id);