| use syntax::ext::base; |
| use syntax::feature_gate; |
| use syntax::print; |
| use syntax::tokenstream; |
| use syntax_pos; |
| |
| pub fn expand_syntax_ext<'cx>(cx: &'cx mut base::ExtCtxt, |
| sp: syntax_pos::Span, |
| tts: &[tokenstream::TokenTree]) |
| -> Box<dyn base::MacResult + 'cx> { |
| if !cx.ecfg.enable_log_syntax() { |
| feature_gate::emit_feature_err(&cx.parse_sess, |
| "log_syntax", |
| sp, |
| feature_gate::GateIssue::Language, |
| feature_gate::EXPLAIN_LOG_SYNTAX); |
| } |
| |
| 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) |
| } |