bring back #[derive(Show)] with a deprecation warning

Jorge Aparicio · Jorge Aparicio · commit a6f9180fd61f · 2015-01-29T07:49:02.000-05:00
diff --git a/src/libsyntax/ext/deriving/mod.rs b/src/libsyntax/ext/deriving/mod.rs
@@ -107,6 +107,14 @@ pub fn expand_meta_derive(cx: &mut ExtCtxt,
 
                             "Rand" => expand!(rand::expand_deriving_rand),
 
+                            "Show" => {
+                                cx.span_warn(titem.span,
+                                             "derive(Show) is deprecated \
+                                              in favor of derive(Debug)");
+
+                                expand!(show::expand_deriving_show)
+                            },
+
                             "Debug" => expand!(show::expand_deriving_show),
 
                             "Default" => expand!(default::expand_deriving_default),
