syntax_data: {"ast_node_type":"other","tokens":[{"end":36,"kind":"keyword","start":0,"text":"body:"}]}
source_snippet:         body: &'tcx hir::Body<'tcx>,
context_before:         fn_decl: &'tcx hir::FnDecl<'tcx>,
context_after:     ) -> impl Iterator<Item = Param<'tcx>> {