// Check that we are refusing to match on complex nonterminals for which tokens are // unavailable and we'd have to go through AST comparisons. #![feature(decl_macro)] macro simple_nonterminal($nt_ident: ident, $nt_lifetime: lifetime, $nt_tt: tt) { macro n(a $nt_ident b $nt_lifetime c $nt_tt d) { struct S; } n!(a $nt_ident b $nt_lifetime c $nt_tt d); } macro complex_nonterminal($nt_item: item) { macro n(a $nt_item b) { struct S; } n!(a $nt_item b); //~ ERROR no rules expected the token `enum E {}` } simple_nonterminal!(a, 'a, (x, y, z)); // OK complex_nonterminal!(enum E {}); fn main() {}