Improve diagnostics

2016-05-19 10:30:34 +00:00 · 2016-05-19 10:30:34 +00:00 · 2e7afd7367
commit 2e7afd7367
parent 7f30eef2ee
1 changed files with 3 additions and 5 deletions
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@ -272,11 +272,9 @@ fn expand_mac_invoc<T: MacroGenerable>(mac: ast::Mac, span: Span, fld: &mut Macr
                let parsed = match opt_parsed {
                    Some(e) => e,
                    None => {
-                        fld.cx.span_err(
-                            pth.span,
-                            &format!("non-expression macro in expression position: {}",
-                                    extname
-                                    ));
+                        let msg = format!("non-{kind} macro in {kind} position: {name}",
+                                          name = extname, kind = T::kind_name());
+                        fld.cx.span_err(pth.span, &msg);
                        return None;
                    }
                };