hygiene: Implement transparent marks

3 files changed, 12 insertions, 1 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 78fa3f326d6..e2424de4d14 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -649,6 +649,7 @@ pub enum SyntaxExtension {
     DeclMacro {
         expander: Box<TTMacroExpander + sync::Sync + sync::Send>,
         def_info: Option<(ast::NodeId, Span)>,
+        is_transparent: bool,
         edition: Edition,
     }
 }
@@ -682,6 +683,13 @@ impl SyntaxExtension {
         }
     }
 
+    pub fn is_transparent(&self) -> bool {
+        match *self {
+            SyntaxExtension::DeclMacro { is_transparent, .. } => is_transparent,
+            _ => false,
+        }
+    }
+
     pub fn edition(&self) -> Edition {
         match *self {
             SyntaxExtension::NormalTT { edition, .. } |
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 38fa92f2c93..e364e145593 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -738,7 +738,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         };
 
         let opt_expanded = match *ext {
-            DeclMacro { ref expander, def_info, edition } => {
+            DeclMacro { ref expander, def_info, edition, .. } => {
                 if let Err(dummy_span) = validate_and_set_expn_info(self, def_info.map(|(_, s)| s),
                                                                     false, false, false, None,
                                                                     edition) {
diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 0c81a68e999..70fc9dada42 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -312,9 +312,12 @@ pub fn compile(sess: &ParseSess, features: &Features, def: &ast::Item, edition:
             edition,
         }
     } else {
+        let is_transparent = attr::contains_name(&def.attrs, "rustc_transparent_macro");
+
         SyntaxExtension::DeclMacro {
             expander,
             def_info: Some((def.id, def.span)),
+            is_transparent,
             edition,
         }
     }