Move `if let` behind a feature gate

1 files changed, 6 insertions, 0 deletions

diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 1c6ee8acc94..fac4244228a 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -71,6 +71,8 @@ static KNOWN_FEATURES: &'static [(&'static str, Status)] = &[
     ("associated_types", Active),
     ("visible_private_types", Active),
 
+    ("if_let", Active),
+
     // if you change this list without updating src/doc/rust.md, cmr will be sad
 
     // A temporary feature gate used to enable parser extensions needed
@@ -356,6 +358,10 @@ impl<'a, 'v> Visitor<'v> for Context<'a> {
                                   e.span,
                                   "tuple indexing is experimental");
             }
+            ast::ExprIfLet(..) => {
+                self.gate_feature("if_let", e.span,
+                                  "`if let` desugaring is experimental");
+            }
             _ => {}
         }
         visit::walk_expr(self, e);