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