Rollup merge of #30420 - petrochenkov:owned2, r=nrc

Part of https://github.com/rust-lang/rust/pull/30095 not causing mysterious segfaults.

r? @nrc

11 files changed, 144 insertions, 177 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index de5595eebee..4b0ec8578c1 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -50,7 +50,6 @@ use codemap::{Span, Spanned, DUMMY_SP, ExpnId};
 use abi::Abi;
 use ext::base;
 use ext::tt::macro_parser;
-use owned_slice::OwnedSlice;
 use parse::token::InternedString;
 use parse::token;
 use parse::lexer;
@@ -261,8 +260,8 @@ impl PathParameters {
     pub fn none() -> PathParameters {
         AngleBracketedParameters(AngleBracketedParameterData {
             lifetimes: Vec::new(),
-            types: OwnedSlice::empty(),
-            bindings: OwnedSlice::empty(),
+            types: P::empty(),
+            bindings: P::empty(),
         })
     }
 
@@ -334,10 +333,10 @@ pub struct AngleBracketedParameterData {
     /// The lifetime parameters for this path segment.
     pub lifetimes: Vec<Lifetime>,
     /// The type parameters for this path segment, if present.
-    pub types: OwnedSlice<P<Ty>>,
+    pub types: P<[P<Ty>]>,
     /// Bindings (equality constraints) on associated types, if present.
     /// E.g., `Foo<A=Bar>`.
-    pub bindings: OwnedSlice<P<TypeBinding>>,
+    pub bindings: P<[P<TypeBinding>]>,
 }
 
 impl AngleBracketedParameterData {
@@ -394,7 +393,7 @@ pub enum TraitBoundModifier {
     Maybe,
 }
 
-pub type TyParamBounds = OwnedSlice<TyParamBound>;
+pub type TyParamBounds = P<[TyParamBound]>;
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct TyParam {
@@ -410,7 +409,7 @@ pub struct TyParam {
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct Generics {
     pub lifetimes: Vec<LifetimeDef>,
-    pub ty_params: OwnedSlice<TyParam>,
+    pub ty_params: P<[TyParam]>,
     pub where_clause: WhereClause,
 }
 
@@ -430,7 +429,7 @@ impl Default for Generics {
     fn default() ->  Generics {
         Generics {
             lifetimes: Vec::new(),
-            ty_params: OwnedSlice::empty(),
+            ty_params: P::empty(),
             where_clause: WhereClause {
                 id: DUMMY_NODE_ID,
                 predicates: Vec::new(),
@@ -466,7 +465,7 @@ pub struct WhereBoundPredicate {
     /// The type being bounded
     pub bounded_ty: P<Ty>,
     /// Trait and lifetime bounds (`Clone+Send+'static`)
-    pub bounds: OwnedSlice<TyParamBound>,
+    pub bounds: TyParamBounds,
 }
 
 /// A lifetime predicate, e.g. `'a: 'b+'c`
diff --git a/src/libsyntax/ast_util.rs b/src/libsyntax/ast_util.rs
index 3d3d5347749..d38b771814c 100644
--- a/src/libsyntax/ast_util.rs
+++ b/src/libsyntax/ast_util.rs
@@ -12,7 +12,6 @@ use ast::*;
 use ast;
 use codemap;
 use codemap::Span;
-use owned_slice::OwnedSlice;
 use parse::token;
 use print::pprust;
 use ptr::P;
@@ -43,8 +42,8 @@ pub fn ident_to_path(s: Span, identifier: Ident) -> Path {
                 identifier: identifier,
                 parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
                     lifetimes: Vec::new(),
-                    types: OwnedSlice::empty(),
-                    bindings: OwnedSlice::empty(),
+                    types: P::empty(),
+                    bindings: P::empty(),
                 })
             }
         ),
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index cdc9cb02453..46a39b98058 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -14,7 +14,6 @@ use ast;
 use attr;
 use codemap::{Span, respan, Spanned, DUMMY_SP, Pos};
 use ext::base::ExtCtxt;
-use owned_slice::OwnedSlice;
 use parse::token::special_idents;
 use parse::token::InternedString;
 use parse::token;
@@ -56,7 +55,7 @@ pub trait AstBuilder {
 
     fn ty(&self, span: Span, ty: ast::Ty_) -> P<ast::Ty>;
     fn ty_path(&self, ast::Path) -> P<ast::Ty>;
-    fn ty_sum(&self, ast::Path, OwnedSlice<ast::TyParamBound>) -> P<ast::Ty>;
+    fn ty_sum(&self, ast::Path, ast::TyParamBounds) -> P<ast::Ty>;
     fn ty_ident(&self, span: Span, idents: ast::Ident) -> P<ast::Ty>;
 
     fn ty_rptr(&self, span: Span,
@@ -70,13 +69,13 @@ pub trait AstBuilder {
     fn ty_option(&self, ty: P<ast::Ty>) -> P<ast::Ty>;
     fn ty_infer(&self, sp: Span) -> P<ast::Ty>;
 
-    fn ty_vars(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> ;
-    fn ty_vars_global(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> ;
+    fn ty_vars(&self, ty_params: &P<[ast::TyParam]>) -> Vec<P<ast::Ty>> ;
+    fn ty_vars_global(&self, ty_params: &P<[ast::TyParam]>) -> Vec<P<ast::Ty>> ;
 
     fn typaram(&self,
                span: Span,
                id: ast::Ident,
-               bounds: OwnedSlice<ast::TyParamBound>,
+               bounds: ast::TyParamBounds,
                default: Option<P<ast::Ty>>) -> ast::TyParam;
 
     fn trait_ref(&self, path: ast::Path) -> ast::TraitRef;
@@ -331,8 +330,8 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
             identifier: last_identifier,
             parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
                 lifetimes: lifetimes,
-                types: OwnedSlice::from_vec(types),
-                bindings: OwnedSlice::from_vec(bindings),
+                types: P::from_vec(types),
+                bindings: P::from_vec(bindings),
             })
         });
         ast::Path {
@@ -369,8 +368,8 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
             identifier: ident,
             parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
                 lifetimes: lifetimes,
-                types: OwnedSlice::from_vec(types),
-                bindings: OwnedSlice::from_vec(bindings),
+                types: P::from_vec(types),
+                bindings: P::from_vec(bindings),
             })
         });
 
@@ -399,7 +398,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         self.ty(path.span, ast::TyPath(None, path))
     }
 
-    fn ty_sum(&self, path: ast::Path, bounds: OwnedSlice<ast::TyParamBound>) -> P<ast::Ty> {
+    fn ty_sum(&self, path: ast::Path, bounds: ast::TyParamBounds) -> P<ast::Ty> {
         self.ty(path.span,
                 ast::TyObjectSum(self.ty_path(path),
                                  bounds))
@@ -448,7 +447,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
     fn typaram(&self,
                span: Span,
                id: ast::Ident,
-               bounds: OwnedSlice<ast::TyParamBound>,
+               bounds: ast::TyParamBounds,
                default: Option<P<ast::Ty>>) -> ast::TyParam {
         ast::TyParam {
             ident: id,
@@ -462,11 +461,11 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
     // these are strange, and probably shouldn't be used outside of
     // pipes. Specifically, the global version possible generates
     // incorrect code.
-    fn ty_vars(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> {
+    fn ty_vars(&self, ty_params: &P<[ast::TyParam]>) -> Vec<P<ast::Ty>> {
         ty_params.iter().map(|p| self.ty_ident(DUMMY_SP, p.ident)).collect()
     }
 
-    fn ty_vars_global(&self, ty_params: &OwnedSlice<ast::TyParam>) -> Vec<P<ast::Ty>> {
+    fn ty_vars_global(&self, ty_params: &P<[ast::TyParam]>) -> Vec<P<ast::Ty>> {
         ty_params
             .iter()
             .map(|p| self.ty_path(self.path_global(DUMMY_SP, vec!(p.ident))))
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index cd976884d2f..cd2210c71b8 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -23,7 +23,6 @@ use ast;
 use attr::{ThinAttributes, ThinAttributesExt};
 use ast_util;
 use codemap::{respan, Span, Spanned};
-use owned_slice::OwnedSlice;
 use parse::token;
 use ptr::P;
 use util::small_vector::SmallVector;
@@ -233,7 +232,7 @@ pub trait Folder : Sized {
         noop_fold_ty_param(tp, self)
     }
 
-    fn fold_ty_params(&mut self, tps: OwnedSlice<TyParam>) -> OwnedSlice<TyParam> {
+    fn fold_ty_params(&mut self, tps: P<[TyParam]>) -> P<[TyParam]> {
         noop_fold_ty_params(tps, self)
     }
 
@@ -257,13 +256,13 @@ pub trait Folder : Sized {
         noop_fold_opt_lifetime(o_lt, self)
     }
 
-    fn fold_opt_bounds(&mut self, b: Option<OwnedSlice<TyParamBound>>)
-                       -> Option<OwnedSlice<TyParamBound>> {
+    fn fold_opt_bounds(&mut self, b: Option<TyParamBounds>)
+                       -> Option<TyParamBounds> {
         noop_fold_opt_bounds(b, self)
     }
 
-    fn fold_bounds(&mut self, b: OwnedSlice<TyParamBound>)
-                       -> OwnedSlice<TyParamBound> {
+    fn fold_bounds(&mut self, b: TyParamBounds)
+                       -> TyParamBounds {
         noop_fold_bounds(b, self)
     }
 
@@ -714,8 +713,8 @@ pub fn noop_fold_ty_param<T: Folder>(tp: TyParam, fld: &mut T) -> TyParam {
     }
 }
 
-pub fn noop_fold_ty_params<T: Folder>(tps: OwnedSlice<TyParam>, fld: &mut T)
-                                      -> OwnedSlice<TyParam> {
+pub fn noop_fold_ty_params<T: Folder>(tps: P<[TyParam]>, fld: &mut T)
+                                      -> P<[TyParam]> {
     tps.move_map(|tp| fld.fold_ty_param(tp))
 }
 
@@ -871,8 +870,8 @@ pub fn noop_fold_mt<T: Folder>(MutTy {ty, mutbl}: MutTy, folder: &mut T) -> MutT
     }
 }
 
-pub fn noop_fold_opt_bounds<T: Folder>(b: Option<OwnedSlice<TyParamBound>>, folder: &mut T)
-                                       -> Option<OwnedSlice<TyParamBound>> {
+pub fn noop_fold_opt_bounds<T: Folder>(b: Option<TyParamBounds>, folder: &mut T)
+                                       -> Option<TyParamBounds> {
     b.map(|bounds| folder.fold_bounds(bounds))
 }
 
diff --git a/src/libsyntax/owned_slice.rs b/src/libsyntax/owned_slice.rs
index 83369689a94..33a3d578598 100644
--- a/src/libsyntax/owned_slice.rs
+++ b/src/libsyntax/owned_slice.rs
@@ -8,100 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::default::Default;
-use std::fmt;
-use std::iter::{IntoIterator, FromIterator};
-use std::ops::Deref;
-use std::slice;
-use std::vec;
-use serialize::{Encodable, Decodable, Encoder, Decoder};
-
-/// A non-growable owned slice. This is a separate type to allow the
-/// representation to change.
-#[derive(Hash, PartialEq, Eq, PartialOrd, Ord)]
-pub struct OwnedSlice<T> {
-    data: Box<[T]>
-}
-
-impl<T:fmt::Debug> fmt::Debug for OwnedSlice<T> {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        self.data.fmt(fmt)
-    }
-}
-
-impl<T> OwnedSlice<T> {
-    pub fn empty() -> OwnedSlice<T> {
-        OwnedSlice  { data: Box::new([]) }
-    }
-
-    #[inline(never)]
-    pub fn from_vec(v: Vec<T>) -> OwnedSlice<T> {
-        OwnedSlice { data: v.into_boxed_slice() }
-    }
-
-    #[inline(never)]
-    pub fn into_vec(self) -> Vec<T> {
-        self.data.into_vec()
-    }
-
-    pub fn as_slice<'a>(&'a self) -> &'a [T] {
-        &*self.data
-    }
-
-    pub fn move_iter(self) -> vec::IntoIter<T> {
-        self.into_vec().into_iter()
-    }
-
-    pub fn map<U, F: FnMut(&T) -> U>(&self, f: F) -> OwnedSlice<U> {
-        self.iter().map(f).collect()
-    }
-}
-
-impl<T> Deref for OwnedSlice<T> {
-    type Target = [T];
-
-    fn deref(&self) -> &[T] {
-        self.as_slice()
-    }
-}
-
-impl<T> Default for OwnedSlice<T> {
-    fn default() -> OwnedSlice<T> {
-        OwnedSlice::empty()
-    }
-}
-
-impl<T: Clone> Clone for OwnedSlice<T> {
-    fn clone(&self) -> OwnedSlice<T> {
-        OwnedSlice::from_vec(self.to_vec())
-    }
-}
-
-impl<T> FromIterator<T> for OwnedSlice<T> {
-    fn from_iter<I: IntoIterator<Item=T>>(iter: I) -> OwnedSlice<T> {
-        OwnedSlice::from_vec(iter.into_iter().collect())
-    }
-}
-
-impl<'a, T> IntoIterator for &'a OwnedSlice<T> {
-    type Item = &'a T;
-    type IntoIter = slice::Iter<'a, T>;
-    fn into_iter(self) -> Self::IntoIter {
-        self.data.into_iter()
-    }
-}
-
-impl<T: Encodable> Encodable for OwnedSlice<T> {
-    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
-        Encodable::encode(&**self, s)
-    }
-}
-
-impl<T: Decodable> Decodable for OwnedSlice<T> {
-    fn decode<D: Decoder>(d: &mut D) -> Result<OwnedSlice<T>, D::Error> {
-        Ok(OwnedSlice::from_vec(match Decodable::decode(d) {
-            Ok(t) => t,
-            Err(e) => return Err(e)
-        }))
-    }
-}
+/// A non-growable owned slice.
+#[unstable(feature = "rustc_private", issue = "0")]
+#[rustc_deprecated(since = "1.7.0", reason = "use `ptr::P<[T]>` instead")]
+pub type OwnedSlice<T> = ::ptr::P<[T]>;
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index ed87961e7f3..cff106f838a 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -671,7 +671,6 @@ mod tests {
     use super::*;
     use std::rc::Rc;
     use codemap::{Span, BytePos, Pos, Spanned, NO_EXPANSION};
-    use owned_slice::OwnedSlice;
     use ast::{self, TokenTree};
     use abi;
     use attr::{first_attr_value_str_by_name, AttrMetaMethods};
@@ -947,7 +946,7 @@ mod tests {
                                     abi::Rust,
                                     ast::Generics{ // no idea on either of these:
                                         lifetimes: Vec::new(),
-                                        ty_params: OwnedSlice::empty(),
+                                        ty_params: P::empty(),
                                         where_clause: ast::WhereClause {
                                             id: ast::DUMMY_NODE_ID,
                                             predicates: Vec::new(),
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index b8c4d8d63b5..ebfcf8c5180 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -50,7 +50,7 @@ use ast::{SelfExplicit, SelfRegion, SelfStatic, SelfValue};
 use ast::{Delimited, SequenceRepetition, TokenTree, TraitItem, TraitRef};
 use ast::{Ty, Ty_, TypeBinding, TyMac};
 use ast::{TyFixedLengthVec, TyBareFn, TyTypeof, TyInfer};
-use ast::{TyParam, TyParamBound, TyParen, TyPath, TyPtr};
+use ast::{TyParam, TyParamBounds, TyParen, TyPath, TyPtr};
 use ast::{TyRptr, TyTup, TyU32, TyVec};
 use ast::TypeTraitItem;
 use ast::{UnnamedField, UnsafeBlock};
@@ -73,7 +73,6 @@ use parse::{new_sub_parser_from_file, ParseSess};
 use util::parser::{AssocOp, Fixity};
 use print::pprust;
 use ptr::P;
-use owned_slice::OwnedSlice;
 use parse::PResult;
 
 use std::collections::HashSet;
@@ -751,7 +750,7 @@ impl<'a> Parser<'a> {
     pub fn parse_seq_to_before_gt_or_return<T, F>(&mut self,
                                                   sep: Option<token::Token>,
                                                   mut f: F)
-                                                  -> PResult<(OwnedSlice<T>, bool)> where
+                                                  -> PResult<(P<[T]>, bool)> where
         F: FnMut(&mut Parser) -> PResult<Option<T>>,
     {
         let mut v = Vec::new();
@@ -772,7 +771,7 @@ impl<'a> Parser<'a> {
             if i % 2 == 0 {
                 match try!(f(self)) {
                     Some(result) => v.push(result),
-                    None => return Ok((OwnedSlice::from_vec(v), true))
+                    None => return Ok((P::from_vec(v), true))
                 }
             } else {
                 if let Some(t) = sep.as_ref() {
@@ -781,7 +780,7 @@ impl<'a> Parser<'a> {
 
             }
         }
-        return Ok((OwnedSlice::from_vec(v), false));
+        return Ok((P::from_vec(v), false));
     }
 
     /// Parse a sequence bracketed by '<' and '>', stopping
@@ -789,7 +788,7 @@ impl<'a> Parser<'a> {
     pub fn parse_seq_to_before_gt<T, F>(&mut self,
                                         sep: Option<token::Token>,
                                         mut f: F)
-                                        -> PResult<OwnedSlice<T>> where
+                                        -> PResult<P<[T]>> where
         F: FnMut(&mut Parser) -> PResult<T>,
     {
         let (result, returned) = try!(self.parse_seq_to_before_gt_or_return(sep,
@@ -801,7 +800,7 @@ impl<'a> Parser<'a> {
     pub fn parse_seq_to_gt<T, F>(&mut self,
                                  sep: Option<token::Token>,
                                  f: F)
-                                 -> PResult<OwnedSlice<T>> where
+                                 -> PResult<P<[T]>> where
         F: FnMut(&mut Parser) -> PResult<T>,
     {
         let v = try!(self.parse_seq_to_before_gt(sep, f));
@@ -812,7 +811,7 @@ impl<'a> Parser<'a> {
     pub fn parse_seq_to_gt_or_return<T, F>(&mut self,
                                            sep: Option<token::Token>,
                                            f: F)
-                                           -> PResult<(OwnedSlice<T>, bool)> where
+                                           -> PResult<(P<[T]>, bool)> where
         F: FnMut(&mut Parser) -> PResult<Option<T>>,
     {
         let (v, returned) = try!(self.parse_seq_to_before_gt_or_return(sep, f));
@@ -1076,7 +1075,7 @@ impl<'a> Parser<'a> {
             let other_bounds = if try!(self.eat(&token::BinOp(token::Plus)) ){
                 try!(self.parse_ty_param_bounds(BoundParsingMode::Bare))
             } else {
-                OwnedSlice::empty()
+                P::empty()
             };
             let all_bounds =
                 Some(TraitTyParamBound(poly_trait_ref, TraitBoundModifier::None)).into_iter()
@@ -1709,8 +1708,8 @@ impl<'a> Parser<'a> {
 
                 ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
                     lifetimes: lifetimes,
-                    types: OwnedSlice::from_vec(types),
-                    bindings: OwnedSlice::from_vec(bindings),
+                    types: P::from_vec(types),
+                    bindings: P::from_vec(bindings),
                 })
             } else if try!(self.eat(&token::OpenDelim(token::Paren)) ){
                 let lo = self.last_span.lo;
@@ -1773,8 +1772,8 @@ impl<'a> Parser<'a> {
                     identifier: identifier,
                     parameters: ast::AngleBracketedParameters(ast::AngleBracketedParameterData {
                         lifetimes: lifetimes,
-                        types: OwnedSlice::from_vec(types),
-                        bindings: OwnedSlice::from_vec(bindings),
+                        types: P::from_vec(types),
+                        bindings: P::from_vec(bindings),
                     }),
                 });
 
@@ -3882,10 +3881,10 @@ impl<'a> Parser<'a> {
     // otherwise returns empty list.
     fn parse_colon_then_ty_param_bounds(&mut self,
                                         mode: BoundParsingMode)
-                                        -> PResult<OwnedSlice<TyParamBound>>
+                                        -> PResult<TyParamBounds>
     {
         if !try!(self.eat(&token::Colon) ){
-            Ok(OwnedSlice::empty())
+            Ok(P::empty())
         } else {
             self.parse_ty_param_bounds(mode)
         }
@@ -3897,7 +3896,7 @@ impl<'a> Parser<'a> {
     // and     bound     = 'region | trait_ref
     fn parse_ty_param_bounds(&mut self,
                              mode: BoundParsingMode)
-                             -> PResult<OwnedSlice<TyParamBound>>
+                             -> PResult<TyParamBounds>
     {
         let mut result = vec!();
         loop {
@@ -3939,7 +3938,7 @@ impl<'a> Parser<'a> {
             }
         }
 
-        return Ok(OwnedSlice::from_vec(result));
+        return Ok(P::from_vec(result));
     }
 
     /// Matches typaram = IDENT (`?` unbound)? optbounds ( EQ ty )?
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 08448f25187..1f296dc5d59 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -17,7 +17,6 @@ use ast::Attribute;
 use attr::ThinAttributesExt;
 use util::parser::AssocOp;
 use attr;
-use owned_slice::OwnedSlice;
 use attr::{AttrMetaMethods, AttributeMethods};
 use codemap::{self, CodeMap, BytePos};
 use errors;
@@ -1001,7 +1000,7 @@ impl<'a> State<'a> {
             ast::TyBareFn(ref f) => {
                 let generics = ast::Generics {
                     lifetimes: f.lifetimes.clone(),
-                    ty_params: OwnedSlice::empty(),
+                    ty_params: P::empty(),
                     where_clause: ast::WhereClause {
                         id: ast::DUMMY_NODE_ID,
                         predicates: Vec::new(),
@@ -3024,7 +3023,7 @@ impl<'a> State<'a> {
         }
         let generics = ast::Generics {
             lifetimes: Vec::new(),
-            ty_params: OwnedSlice::empty(),
+            ty_params: P::empty(),
             where_clause: ast::WhereClause {
                 id: ast::DUMMY_NODE_ID,
                 predicates: Vec::new(),
diff --git a/src/libsyntax/ptr.rs b/src/libsyntax/ptr.rs
index 83e321f110c..1be0b08086d 100644
--- a/src/libsyntax/ptr.rs
+++ b/src/libsyntax/ptr.rs
@@ -37,14 +37,15 @@
 //!   Moreover, a switch to, e.g. `P<'a, T>` would be easy and mostly automated.
 
 use std::fmt::{self, Display, Debug};
-use std::hash::{Hash, Hasher};
+use std::iter::FromIterator;
 use std::ops::Deref;
-use std::ptr;
+use std::{ptr, slice, vec};
 
 use serialize::{Encodable, Decodable, Encoder, Decoder};
 
 /// An owned smart pointer.
-pub struct P<T> {
+#[derive(Hash, PartialEq, Eq, PartialOrd, Ord)]
+pub struct P<T: ?Sized> {
     ptr: Box<T>
 }
 
@@ -92,14 +93,6 @@ impl<T: 'static + Clone> Clone for P<T> {
     }
 }
 
-impl<T: PartialEq> PartialEq for P<T> {
-    fn eq(&self, other: &P<T>) -> bool {
-        **self == **other
-    }
-}
-
-impl<T: Eq> Eq for P<T> {}
-
 impl<T: Debug> Debug for P<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         Debug::fmt(&**self, f)
@@ -111,19 +104,12 @@ impl<T: Display> Display for P<T> {
     }
 }
 
-#[stable(feature = "rust1", since = "1.0.0")]
 impl<T> fmt::Pointer for P<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Pointer::fmt(&self.ptr, f)
     }
 }
 
-impl<T: Hash> Hash for P<T> {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        (**self).hash(state);
-    }
-}
-
 impl<T: 'static + Decodable> Decodable for P<T> {
     fn decode<D: Decoder>(d: &mut D) -> Result<P<T>, D::Error> {
         Decodable::decode(d).map(P)
@@ -135,3 +121,87 @@ impl<T: Encodable> Encodable for P<T> {
         (**self).encode(s)
     }
 }
+
+
+impl<T:fmt::Debug> fmt::Debug for P<[T]> {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        self.ptr.fmt(fmt)
+    }
+}
+
+impl<T> P<[T]> {
+    pub fn empty() -> P<[T]> {
+        P { ptr: Default::default() }
+    }
+
+    #[inline(never)]
+    pub fn from_vec(v: Vec<T>) -> P<[T]> {
+        P { ptr: v.into_boxed_slice() }
+    }
+
+    #[inline(never)]
+    pub fn into_vec(self) -> Vec<T> {
+        self.ptr.into_vec()
+    }
+
+    pub fn as_slice<'a>(&'a self) -> &'a [T] {
+        &*self.ptr
+    }
+
+    pub fn move_iter(self) -> vec::IntoIter<T> {
+        self.into_vec().into_iter()
+    }
+
+    pub fn map<U, F: FnMut(&T) -> U>(&self, f: F) -> P<[U]> {
+        self.iter().map(f).collect()
+    }
+}
+
+impl<T> Deref for P<[T]> {
+    type Target = [T];
+
+    fn deref(&self) -> &[T] {
+        self.as_slice()
+    }
+}
+
+impl<T> Default for P<[T]> {
+    fn default() -> P<[T]> {
+        P::empty()
+    }
+}
+
+impl<T: Clone> Clone for P<[T]> {
+    fn clone(&self) -> P<[T]> {
+        P::from_vec(self.to_vec())
+    }
+}
+
+impl<T> FromIterator<T> for P<[T]> {
+    fn from_iter<I: IntoIterator<Item=T>>(iter: I) -> P<[T]> {
+        P::from_vec(iter.into_iter().collect())
+    }
+}
+
+impl<'a, T> IntoIterator for &'a P<[T]> {
+    type Item = &'a T;
+    type IntoIter = slice::Iter<'a, T>;
+    fn into_iter(self) -> Self::IntoIter {
+        self.ptr.into_iter()
+    }
+}
+
+impl<T: Encodable> Encodable for P<[T]> {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        Encodable::encode(&**self, s)
+    }
+}
+
+impl<T: Decodable> Decodable for P<[T]> {
+    fn decode<D: Decoder>(d: &mut D) -> Result<P<[T]>, D::Error> {
+        Ok(P::from_vec(match Decodable::decode(d) {
+            Ok(t) => t,
+            Err(e) => return Err(e)
+        }))
+    }
+}
diff --git a/src/libsyntax/test.rs b/src/libsyntax/test.rs
index 9e1d80b3f0d..9a6d1f8fdab 100644
--- a/src/libsyntax/test.rs
+++ b/src/libsyntax/test.rs
@@ -32,7 +32,6 @@ use ext::expand::ExpansionConfig;
 use fold::Folder;
 use util::move_map::MoveMap;
 use fold;
-use owned_slice::OwnedSlice;
 use parse::token::{intern, InternedString};
 use parse::{token, ParseSess};
 use print::pprust;
diff --git a/src/libsyntax/util/move_map.rs b/src/libsyntax/util/move_map.rs
index 95c24c66630..e1078b719bf 100644
--- a/src/libsyntax/util/move_map.rs
+++ b/src/libsyntax/util/move_map.rs
@@ -8,8 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use owned_slice::OwnedSlice;
-
 use std::ptr;
 
 pub trait MoveMap<T>: Sized {
@@ -69,11 +67,11 @@ impl<T> MoveMap<T> for Vec<T> {
     }
 }
 
-impl<T> MoveMap<T> for OwnedSlice<T> {
+impl<T> MoveMap<T> for ::ptr::P<[T]> {
     fn move_flat_map<F, I>(self, f: F) -> Self
         where F: FnMut(T) -> I,
               I: IntoIterator<Item=T>
     {
-        OwnedSlice::from_vec(self.into_vec().move_flat_map(f))
+        ::ptr::P::from_vec(self.into_vec().move_flat_map(f))
     }
 }