rollup merge of #23794: brson/slicegate

Conflicts:
	src/test/run-pass/issue-13027.rs

2 files changed, 9 insertions, 0 deletions

diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 70f43776ff0..c6e6e749860 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -147,6 +147,9 @@ const KNOWN_FEATURES: &'static [(&'static str, &'static str, Status)] = &[
     // below (it has to be checked before expansion possibly makes
     // macros disappear).
     ("allow_internal_unstable", "1.0.0", Active),
+
+    // #23121. Array patterns have some hazards yet.
+    ("slice_patterns", "1.0.0", Active),
 ];
 // (changing above list without updating src/doc/reference.md makes @cmr sad)
 
@@ -628,6 +631,11 @@ impl<'a, 'v> Visitor<'v> for PostExpansionVisitor<'a> {
                                    but at the end of a slice (e.g. \
                                    `[0, ..xs, 0]` are experimental")
             }
+            ast::PatVec(..) => {
+                self.gate_feature("slice_patterns",
+                                  pattern.span,
+                                  "slice pattern syntax is experimental");
+            }
             ast::PatBox(..) => {
                 self.gate_feature("box_patterns",
                                   pattern.span,
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index 7d6dc3112ad..c471d9e3179 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -39,6 +39,7 @@
 #![feature(str_char)]
 #![feature(convert)]
 #![feature(into_cow)]
+#![feature(slice_patterns)]
 
 extern crate arena;
 extern crate fmt_macros;