use rustc_ast::tokenstream::TokenStream; use rustc_ast_pretty::pprust; use rustc_expand::base; pub fn expand_log_syntax<'cx>( _cx: &'cx mut base::ExtCtxt<'_>, sp: rustc_span::Span, tts: TokenStream, ) -> Box { println!("{}", pprust::tts_to_string(&tts)); // any so that `log_syntax` can be invoked as an expression and item. base::DummyResult::any_valid(sp) }