Implement &-patterns

Closes #2855

4 files changed, 29 insertions, 14 deletions

diff --git a/src/rustc/middle/check_alt.rs b/src/rustc/middle/check_alt.rs
index 364cd4890ab..b4a5db2baa4 100644
--- a/src/rustc/middle/check_alt.rs
+++ b/src/rustc/middle/check_alt.rs
@@ -235,7 +235,7 @@ fn pat_ctor_id(tcx: ty::ctxt, p: @pat) -> Option<ctor> {
       pat_range(lo, hi) => {
         Some(range(eval_const_expr(tcx, lo), eval_const_expr(tcx, hi)))
       }
-      pat_box(_) | pat_uniq(_) | pat_rec(_, _) | pat_tup(_) |
+      pat_box(_) | pat_uniq(_) | pat_rec(_, _) | pat_tup(_) | pat_region(*) |
       pat_struct(*) => {
         Some(single)
       }
@@ -258,8 +258,8 @@ fn is_wild(tcx: ty::ctxt, p: @pat) -> bool {
 
 fn missing_ctor(tcx: ty::ctxt, m: matrix, left_ty: ty::t) -> Option<ctor> {
     match ty::get(left_ty).struct {
-      ty::ty_box(_) | ty::ty_uniq(_) | ty::ty_tup(_) | ty::ty_rec(_) |
-      ty::ty_class(*) => {
+      ty::ty_box(_) | ty::ty_uniq(_) | ty::ty_rptr(*) | ty::ty_tup(_) |
+      ty::ty_rec(_) | ty::ty_class(*) => {
         for m.each |r| {
             if !is_wild(tcx, r[0]) { return None; }
         }
@@ -305,7 +305,7 @@ fn ctor_arity(tcx: ty::ctxt, ctor: ctor, ty: ty::t) -> uint {
     match ty::get(ty).struct {
       ty::ty_tup(fs) => fs.len(),
       ty::ty_rec(fs) => fs.len(),
-      ty::ty_box(_) | ty::ty_uniq(_) => 1u,
+      ty::ty_box(_) | ty::ty_uniq(_) | ty::ty_rptr(*) => 1u,
       ty::ty_enum(eid, _) => {
           let id = match ctor { variant(id) => id,
           _ => fail ~"impossible case" };
@@ -386,7 +386,8 @@ fn specialize(tcx: ty::ctxt, r: ~[@pat], ctor_id: ctor, arity: uint,
         Some(vec::append(args, vec::tail(r)))
       }
       pat_tup(args) => Some(vec::append(args, vec::tail(r))),
-      pat_box(a) | pat_uniq(a) => Some(vec::append(~[a], vec::tail(r))),
+      pat_box(a) | pat_uniq(a) | pat_region(a) =>
+          Some(vec::append(~[a], vec::tail(r))),
       pat_lit(expr) => {
         let e_v = eval_const_expr(tcx, expr);
         let match_ = match ctor_id {
@@ -440,7 +441,8 @@ fn is_refutable(tcx: ty::ctxt, pat: @pat) -> bool {
     }
 
     match pat.node {
-      pat_box(sub) | pat_uniq(sub) | pat_ident(_, _, Some(sub)) => {
+      pat_box(sub) | pat_uniq(sub) | pat_region(sub) |
+      pat_ident(_, _, Some(sub)) => {
         is_refutable(tcx, sub)
       }
       pat_wild | pat_ident(_, _, None) => { false }
diff --git a/src/rustc/middle/mem_categorization.rs b/src/rustc/middle/mem_categorization.rs
index 7440d37ae5d..75868e6300f 100644
--- a/src/rustc/middle/mem_categorization.rs
+++ b/src/rustc/middle/mem_categorization.rs
@@ -898,8 +898,9 @@ impl &mem_categorization_ctxt {
             }
           }
 
-          ast::pat_box(subpat) | ast::pat_uniq(subpat) => {
-            // @p1, ~p1
+          ast::pat_box(subpat) | ast::pat_uniq(subpat) |
+          ast::pat_region(subpat) => {
+            // @p1, ~p1, &p1
             match self.cat_deref(subpat, cmt, 0u, true) {
               Some(subcmt) => {
                 self.cat_pattern(subcmt, subpat, op);
diff --git a/src/rustc/middle/trans/alt.rs b/src/rustc/middle/trans/alt.rs
index fb7c8fae337..e09f9860b58 100644
--- a/src/rustc/middle/trans/alt.rs
+++ b/src/rustc/middle/trans/alt.rs
@@ -914,12 +914,8 @@ fn bind_irrefutable_pat(bcx: block, pat: @ast::pat, val: ValueRef,
                 bcx = bind_irrefutable_pat(bcx, elem, fldptr, make_copy);
             }
         }
-        ast::pat_box(inner) => {
-            let llbox = Load(bcx, val);
-            let unboxed = GEPi(bcx, llbox, [0u, abi::box_field_body]);
-            bcx = bind_irrefutable_pat(bcx, inner, unboxed, true);
-        }
-        ast::pat_uniq(inner) => {
+        ast::pat_box(inner) | ast::pat_uniq(inner) |
+        ast::pat_region(inner) => {
             let llbox = Load(bcx, val);
             let unboxed = GEPi(bcx, llbox, [0u, abi::box_field_body]);
             bcx = bind_irrefutable_pat(bcx, inner, unboxed, true);
diff --git a/src/rustc/middle/typeck/check/alt.rs b/src/rustc/middle/typeck/check/alt.rs
index 0282a9d78c4..2d49714d7d2 100644
--- a/src/rustc/middle/typeck/check/alt.rs
+++ b/src/rustc/middle/typeck/check/alt.rs
@@ -447,6 +447,22 @@ fn check_pat(pcx: pat_ctxt, pat: @ast::pat, expected: ty::t) {
           }
         }
       }
+      ast::pat_region(inner) => {
+        match structure_of(fcx, pat.span, expected) {
+          ty::ty_rptr(_, e_inner) => {
+            check_pat(pcx, inner, e_inner.ty);
+            fcx.write_ty(pat.id, expected);
+          }
+          _ => {
+            tcx.sess.span_fatal(
+                pat.span,
+                ~"mismatched types: expected `" +
+                fcx.infcx().ty_to_str(expected) +
+                ~"` found borrowed pointer");
+          }
+        }
+      }
+
     }
 }