move middle::ty and related modules to middle/ty/

52 files changed, 140 insertions, 154 deletions

diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index b11bf6f80fb..cfeab976e24 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -107,7 +107,6 @@ pub mod front {
 pub mod middle {
     pub mod astconv_util;
     pub mod astencode;
-    pub mod cast;
     pub mod cfg;
     pub mod check_const;
     pub mod check_static_recursion;
@@ -124,7 +123,6 @@ pub mod middle {
     pub mod effect;
     pub mod entry;
     pub mod expr_use_visitor;
-    pub mod fast_reject;
     pub mod free_region;
     pub mod intrinsicck;
     pub mod infer;
@@ -132,7 +130,6 @@ pub mod middle {
     pub mod lang_items;
     pub mod liveness;
     pub mod mem_categorization;
-    pub mod outlives;
     pub mod pat_util;
     pub mod privacy;
     pub mod reachable;
@@ -143,11 +140,6 @@ pub mod middle {
     pub mod subst;
     pub mod traits;
     pub mod ty;
-    pub mod ty_fold;
-    pub mod ty_match;
-    pub mod ty_relate;
-    pub mod ty_walk;
-    pub mod wf;
     pub mod weak_lang_items;
 }
 
diff --git a/src/librustc/middle/astencode.rs b/src/librustc/middle/astencode.rs
index abf2d5f3625..ac2dd545982 100644
--- a/src/librustc/middle/astencode.rs
+++ b/src/librustc/middle/astencode.rs
@@ -27,7 +27,7 @@ use metadata::tydecode;
 use metadata::tydecode::{DefIdSource, NominalType, TypeWithId};
 use metadata::tydecode::{RegionParameter, ClosureSource};
 use metadata::tyencode;
-use middle::cast;
+use middle::ty::cast;
 use middle::check_const::ConstQualif;
 use middle::def;
 use middle::def_id::{DefId, LOCAL_CRATE};
diff --git a/src/librustc/middle/check_const.rs b/src/librustc/middle/check_const.rs
index 37e14428176..48c8cca76b0 100644
--- a/src/librustc/middle/check_const.rs
+++ b/src/librustc/middle/check_const.rs
@@ -24,7 +24,7 @@
 // - It's not possible to take the address of a static item with unsafe interior. This is enforced
 // by borrowck::gather_loans
 
-use middle::cast::{CastKind};
+use middle::ty::cast::{CastKind};
 use middle::const_eval;
 use middle::const_eval::EvalHint::ExprTypeChecked;
 use middle::def;
diff --git a/src/librustc/middle/free_region.rs b/src/librustc/middle/free_region.rs
index c39c3fd3027..2e9e5fafb1d 100644
--- a/src/librustc/middle/free_region.rs
+++ b/src/librustc/middle/free_region.rs
@@ -16,7 +16,7 @@
 //! region outlives another and so forth.
 
 use middle::ty::{self, FreeRegion, Region};
-use middle::wf::ImpliedBound;
+use middle::ty::wf::ImpliedBound;
 use rustc_data_structures::transitive_relation::TransitiveRelation;
 
 #[derive(Clone)]
diff --git a/src/librustc/middle/implicator.rs b/src/librustc/middle/implicator.rs
index b1a4e0270c2..9f33c4df03d 100644
--- a/src/librustc/middle/implicator.rs
+++ b/src/librustc/middle/implicator.rs
@@ -15,7 +15,7 @@ use middle::infer::{InferCtxt, GenericKind};
 use middle::subst::Substs;
 use middle::traits;
 use middle::ty::{self, RegionEscape, ToPredicate, Ty};
-use middle::ty_fold::{TypeFoldable, TypeFolder};
+use middle::ty::fold::{TypeFoldable, TypeFolder};
 
 use syntax::ast;
 use syntax::codemap::Span;
diff --git a/src/librustc/middle/infer/bivariate.rs b/src/librustc/middle/infer/bivariate.rs
index d2268894b20..2d9432b75e7 100644
--- a/src/librustc/middle/infer/bivariate.rs
+++ b/src/librustc/middle/infer/bivariate.rs
@@ -30,7 +30,7 @@ use super::type_variable::{BiTo};
 
 use middle::ty::{self, Ty};
 use middle::ty::TyVar;
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 
 pub struct Bivariate<'a, 'tcx: 'a> {
     fields: CombineFields<'a, 'tcx>
diff --git a/src/librustc/middle/infer/combine.rs b/src/librustc/middle/infer/combine.rs
index 00edd054aa5..3a29fdfae23 100644
--- a/src/librustc/middle/infer/combine.rs
+++ b/src/librustc/middle/infer/combine.rs
@@ -44,9 +44,8 @@ use super::type_variable::{RelationDir, BiTo, EqTo, SubtypeOf, SupertypeOf};
 use middle::ty::{TyVar};
 use middle::ty::{IntType, UintType};
 use middle::ty::{self, Ty, TypeError};
-use middle::ty_fold;
-use middle::ty_fold::{TypeFolder, TypeFoldable};
-use middle::ty_relate::{self, Relate, RelateResult, TypeRelation};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 
 use syntax::codemap::Span;
 use rustc_front::hir;
@@ -56,7 +55,7 @@ pub struct CombineFields<'a, 'tcx: 'a> {
     pub infcx: &'a InferCtxt<'a, 'tcx>,
     pub a_is_expected: bool,
     pub trace: TypeTrace<'tcx>,
-    pub cause: Option<ty_relate::Cause>,
+    pub cause: Option<ty::relate::Cause>,
 }
 
 pub fn super_combine_tys<'a,'tcx:'a,R>(infcx: &InferCtxt<'a, 'tcx>,
@@ -108,12 +107,12 @@ pub fn super_combine_tys<'a,'tcx:'a,R>(infcx: &InferCtxt<'a, 'tcx>,
         // All other cases of inference are errors
         (&ty::TyInfer(_), _) |
         (_, &ty::TyInfer(_)) => {
-            Err(TypeError::Sorts(ty_relate::expected_found(relation, &a, &b)))
+            Err(TypeError::Sorts(ty::relate::expected_found(relation, &a, &b)))
         }
 
 
         _ => {
-            ty_relate::super_relate_tys(relation, a, b)
+            ty::relate::super_relate_tys(relation, a, b)
         }
     }
 }
@@ -293,7 +292,7 @@ struct Generalizer<'cx, 'tcx:'cx> {
     cycle_detected: bool,
 }
 
-impl<'cx, 'tcx> ty_fold::TypeFolder<'tcx> for Generalizer<'cx, 'tcx> {
+impl<'cx, 'tcx> ty::fold::TypeFolder<'tcx> for Generalizer<'cx, 'tcx> {
     fn tcx(&self) -> &ty::ctxt<'tcx> {
         self.infcx.tcx
     }
@@ -319,7 +318,7 @@ impl<'cx, 'tcx> ty_fold::TypeFolder<'tcx> for Generalizer<'cx, 'tcx> {
                 }
             }
             _ => {
-                ty_fold::super_fold_ty(self, t)
+                ty::fold::super_fold_ty(self, t)
             }
         }
     }
@@ -384,7 +383,7 @@ fn int_unification_error<'tcx>(a_is_expected: bool, v: (ty::IntVarValue, ty::Int
                                -> ty::TypeError<'tcx>
 {
     let (a, b) = v;
-    TypeError::IntMismatch(ty_relate::expected_found_bool(a_is_expected, &a, &b))
+    TypeError::IntMismatch(ty::relate::expected_found_bool(a_is_expected, &a, &b))
 }
 
 fn float_unification_error<'tcx>(a_is_expected: bool,
@@ -392,5 +391,5 @@ fn float_unification_error<'tcx>(a_is_expected: bool,
                                  -> ty::TypeError<'tcx>
 {
     let (a, b) = v;
-    TypeError::FloatMismatch(ty_relate::expected_found_bool(a_is_expected, &a, &b))
+    TypeError::FloatMismatch(ty::relate::expected_found_bool(a_is_expected, &a, &b))
 }
diff --git a/src/librustc/middle/infer/equate.rs b/src/librustc/middle/infer/equate.rs
index cbbf73d9420..07ce4688c06 100644
--- a/src/librustc/middle/infer/equate.rs
+++ b/src/librustc/middle/infer/equate.rs
@@ -15,7 +15,7 @@ use super::type_variable::{EqTo};
 
 use middle::ty::{self, Ty};
 use middle::ty::TyVar;
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 
 pub struct Equate<'a, 'tcx: 'a> {
     fields: CombineFields<'a, 'tcx>
diff --git a/src/librustc/middle/infer/freshen.rs b/src/librustc/middle/infer/freshen.rs
index c72a4fc0db3..0bae3cd2d86 100644
--- a/src/librustc/middle/infer/freshen.rs
+++ b/src/librustc/middle/infer/freshen.rs
@@ -31,9 +31,8 @@
 //! inferencer knows "so far".
 
 use middle::ty::{self, Ty, HasTypeFlags};
-use middle::ty_fold;
-use middle::ty_fold::TypeFoldable;
-use middle::ty_fold::TypeFolder;
+use middle::ty::fold::TypeFoldable;
+use middle::ty::fold::TypeFolder;
 use std::collections::hash_map::{self, Entry};
 
 use super::InferCtxt;
@@ -170,7 +169,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for TypeFreshener<'a, 'tcx> {
             ty::TyTuple(..) |
             ty::TyProjection(..) |
             ty::TyParam(..) => {
-                ty_fold::super_fold_ty(self, t)
+                ty::fold::super_fold_ty(self, t)
             }
         }
     }
diff --git a/src/librustc/middle/infer/glb.rs b/src/librustc/middle/infer/glb.rs
index d6b03266b1f..0035f31e8db 100644
--- a/src/librustc/middle/infer/glb.rs
+++ b/src/librustc/middle/infer/glb.rs
@@ -15,7 +15,7 @@ use super::lattice::{self, LatticeDir};
 use super::Subtype;
 
 use middle::ty::{self, Ty};
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 
 /// "Greatest lower bound" (common subtype)
 pub struct Glb<'a, 'tcx: 'a> {
diff --git a/src/librustc/middle/infer/higher_ranked/mod.rs b/src/librustc/middle/infer/higher_ranked/mod.rs
index 0c539a5d0e0..10a31f0e657 100644
--- a/src/librustc/middle/infer/higher_ranked/mod.rs
+++ b/src/librustc/middle/infer/higher_ranked/mod.rs
@@ -15,8 +15,8 @@ use super::{CombinedSnapshot, InferCtxt, HigherRankedType, SkolemizationMap};
 use super::combine::CombineFields;
 
 use middle::ty::{self, TypeError, Binder};
-use middle::ty_fold::{self, TypeFoldable};
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::fold::TypeFoldable;
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 use syntax::codemap::Span;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 
@@ -358,7 +358,7 @@ fn fold_regions_in<'tcx, T, F>(tcx: &ty::ctxt<'tcx>,
     where T: TypeFoldable<'tcx>,
           F: FnMut(ty::Region, ty::DebruijnIndex) -> ty::Region,
 {
-    ty_fold::fold_regions(tcx, unbound_value, &mut false, |region, current_depth| {
+    ty::fold::fold_regions(tcx, unbound_value, &mut false, |region, current_depth| {
         // we should only be encountering "escaping" late-bound regions here,
         // because the ones at the current level should have been replaced
         // with fresh variables
@@ -438,7 +438,7 @@ impl<'a,'tcx> InferCtxtExt for InferCtxt<'a,'tcx> {
 
         let mut escaping_region_vars = FnvHashSet();
         for ty in &escaping_types {
-            ty_fold::collect_regions(self.tcx, ty, &mut escaping_region_vars);
+            ty::fold::collect_regions(self.tcx, ty, &mut escaping_region_vars);
         }
 
         region_vars.retain(|&region_vid| {
@@ -468,7 +468,7 @@ pub fn skolemize_late_bound_regions<'a,'tcx,T>(infcx: &InferCtxt<'a,'tcx>,
      * details.
      */
 
-    let (result, map) = ty_fold::replace_late_bound_regions(infcx.tcx, binder, |br| {
+    let (result, map) = ty::fold::replace_late_bound_regions(infcx.tcx, binder, |br| {
         infcx.region_vars.new_skolemized(br, &snapshot.region_vars_snapshot)
     });
 
@@ -590,7 +590,7 @@ pub fn plug_leaks<'a,'tcx,T>(infcx: &InferCtxt<'a,'tcx>,
     // binder is that we encountered in `value`. The caller is
     // responsible for ensuring that (a) `value` contains at least one
     // binder and (b) that binder is the one we want to use.
-    let result = ty_fold::fold_regions(infcx.tcx, &value, &mut false, |r, current_depth| {
+    let result = ty::fold::fold_regions(infcx.tcx, &value, &mut false, |r, current_depth| {
         match inv_skol_map.get(&r) {
             None => r,
             Some(br) => {
diff --git a/src/librustc/middle/infer/lattice.rs b/src/librustc/middle/infer/lattice.rs
index 7b34fda2406..2a560ec8a1d 100644
--- a/src/librustc/middle/infer/lattice.rs
+++ b/src/librustc/middle/infer/lattice.rs
@@ -34,7 +34,7 @@ use super::InferCtxt;
 
 use middle::ty::TyVar;
 use middle::ty::{self, Ty};
-use middle::ty_relate::{RelateResult, TypeRelation};
+use middle::ty::relate::{RelateResult, TypeRelation};
 
 pub trait LatticeDir<'f,'tcx> : TypeRelation<'f,'tcx> {
     fn infcx(&self) -> &'f InferCtxt<'f, 'tcx>;
diff --git a/src/librustc/middle/infer/lub.rs b/src/librustc/middle/infer/lub.rs
index 9d993ead5ca..238dad65ef0 100644
--- a/src/librustc/middle/infer/lub.rs
+++ b/src/librustc/middle/infer/lub.rs
@@ -15,7 +15,7 @@ use super::lattice::{self, LatticeDir};
 use super::Subtype;
 
 use middle::ty::{self, Ty};
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 
 /// "Least upper bound" (common supertype)
 pub struct Lub<'a, 'tcx: 'a> {
@@ -83,4 +83,3 @@ impl<'a, 'tcx> LatticeDir<'a,'tcx> for Lub<'a, 'tcx> {
         Ok(())
     }
 }
-
diff --git a/src/librustc/middle/infer/mod.rs b/src/librustc/middle/infer/mod.rs
index 4ef96c0f3b4..5b94f5311fd 100644
--- a/src/librustc/middle/infer/mod.rs
+++ b/src/librustc/middle/infer/mod.rs
@@ -32,8 +32,8 @@ use middle::traits::{self, FulfillmentContext, Normalized,
                      SelectionContext, ObligationCause};
 use middle::ty::{TyVid, IntVid, FloatVid, RegionVid, UnconstrainedNumeric};
 use middle::ty::{self, Ty, TypeError, HasTypeFlags};
-use middle::ty_fold::{self, TypeFolder, TypeFoldable};
-use middle::ty_relate::{Relate, RelateResult, TypeRelation};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
+use middle::ty::relate::{Relate, RelateResult, TypeRelation};
 use rustc_data_structures::unify::{self, UnificationTable};
 use std::cell::{RefCell, Ref};
 use std::fmt;
@@ -583,7 +583,7 @@ pub fn drain_fulfillment_cx<'a,'tcx,T>(infcx: &InferCtxt<'a,'tcx>,
 /// Returns an equivalent value with all free regions removed (note
 /// that late-bound regions remain, because they are important for
 /// subtyping, but they are anonymized and normalized as well). This
-/// is a stronger, caching version of `ty_fold::erase_regions`.
+/// is a stronger, caching version of `ty::fold::erase_regions`.
 pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
     where T : TypeFoldable<'tcx>
 {
@@ -603,7 +603,7 @@ pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
                 Some(u) => return u
             }
 
-            let t_norm = ty_fold::super_fold_ty(self, ty);
+            let t_norm = ty::fold::super_fold_ty(self, ty);
             self.tcx().normalized_cache.borrow_mut().insert(ty, t_norm);
             return t_norm;
         }
@@ -612,7 +612,7 @@ pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
             where T : TypeFoldable<'tcx>
         {
             let u = self.tcx().anonymize_late_bound_regions(t);
-            ty_fold::super_fold_binder(self, &u)
+            ty::fold::super_fold_binder(self, &u)
         }
 
         fn fold_region(&mut self, r: ty::Region) -> ty::Region {
@@ -1406,7 +1406,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         -> (T, FnvHashMap<ty::BoundRegion,ty::Region>)
         where T : TypeFoldable<'tcx>
     {
-        ty_fold::replace_late_bound_regions(
+        ty::fold::replace_late_bound_regions(
             self.tcx,
             value,
             |br| self.next_region_var(LateBoundRegion(span, br, lbrct)))
diff --git a/src/librustc/middle/infer/region_inference/mod.rs b/src/librustc/middle/infer/region_inference/mod.rs
index d81f8e0ae90..a62fd8890ba 100644
--- a/src/librustc/middle/infer/region_inference/mod.rs
+++ b/src/librustc/middle/infer/region_inference/mod.rs
@@ -27,7 +27,7 @@ use middle::ty::{self, Ty, TypeError};
 use middle::ty::{BoundRegion, FreeRegion, Region, RegionVid};
 use middle::ty::{ReEmpty, ReStatic, ReFree, ReEarlyBound};
 use middle::ty::{ReLateBound, ReScope, ReVar, ReSkolemized, BrFresh};
-use middle::ty_relate::RelateResult;
+use middle::ty::relate::RelateResult;
 use util::common::indenter;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 
diff --git a/src/librustc/middle/infer/resolve.rs b/src/librustc/middle/infer/resolve.rs
index 9cc9f148ce1..4bcceade775 100644
--- a/src/librustc/middle/infer/resolve.rs
+++ b/src/librustc/middle/infer/resolve.rs
@@ -10,7 +10,7 @@
 
 use super::{InferCtxt, FixupError, FixupResult};
 use middle::ty::{self, Ty, HasTypeFlags};
-use middle::ty_fold::{self, TypeFoldable};
+use middle::ty::fold::{TypeFoldable};
 
 ///////////////////////////////////////////////////////////////////////////
 // OPPORTUNISTIC TYPE RESOLVER
@@ -30,7 +30,7 @@ impl<'a, 'tcx> OpportunisticTypeResolver<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> ty_fold::TypeFolder<'tcx> for OpportunisticTypeResolver<'a, 'tcx> {
+impl<'a, 'tcx> ty::fold::TypeFolder<'tcx> for OpportunisticTypeResolver<'a, 'tcx> {
     fn tcx(&self) -> &ty::ctxt<'tcx> {
         self.infcx.tcx
     }
@@ -40,7 +40,7 @@ impl<'a, 'tcx> ty_fold::TypeFolder<'tcx> for OpportunisticTypeResolver<'a, 'tcx>
             t // micro-optimize -- if there is nothing in this type that this fold affects...
         } else {
             let t0 = self.infcx.shallow_resolve(t);
-            ty_fold::super_fold_ty(self, t0)
+            ty::fold::super_fold_ty(self, t0)
         }
     }
 }
@@ -69,7 +69,7 @@ struct FullTypeResolver<'a, 'tcx:'a> {
     err: Option<FixupError>,
 }
 
-impl<'a, 'tcx> ty_fold::TypeFolder<'tcx> for FullTypeResolver<'a, 'tcx> {
+impl<'a, 'tcx> ty::fold::TypeFolder<'tcx> for FullTypeResolver<'a, 'tcx> {
     fn tcx(&self) -> &ty::ctxt<'tcx> {
         self.infcx.tcx
     }
@@ -98,7 +98,7 @@ impl<'a, 'tcx> ty_fold::TypeFolder<'tcx> for FullTypeResolver<'a, 'tcx> {
                                 t));
                 }
                 _ => {
-                    ty_fold::super_fold_ty(self, t)
+                    ty::fold::super_fold_ty(self, t)
                 }
             }
         }
diff --git a/src/librustc/middle/infer/sub.rs b/src/librustc/middle/infer/sub.rs
index 4d76d613392..155f5f44002 100644
--- a/src/librustc/middle/infer/sub.rs
+++ b/src/librustc/middle/infer/sub.rs
@@ -15,7 +15,7 @@ use super::type_variable::{SubtypeOf, SupertypeOf};
 
 use middle::ty::{self, Ty};
 use middle::ty::TyVar;
-use middle::ty_relate::{Cause, Relate, RelateResult, TypeRelation};
+use middle::ty::relate::{Cause, Relate, RelateResult, TypeRelation};
 use std::mem;
 
 /// "Greatest lower bound" (common subtype)
diff --git a/src/librustc/middle/subst.rs b/src/librustc/middle/subst.rs
index 7d8a20c42e3..c44891de0a0 100644
--- a/src/librustc/middle/subst.rs
+++ b/src/librustc/middle/subst.rs
@@ -14,7 +14,7 @@ pub use self::ParamSpace::*;
 pub use self::RegionSubsts::*;
 
 use middle::ty::{self, Ty, HasTypeFlags, RegionEscape};
-use middle::ty_fold::{self, TypeFoldable, TypeFolder};
+use middle::ty::fold::{TypeFoldable, TypeFolder};
 
 use std::fmt;
 use std::iter::IntoIterator;
@@ -643,7 +643,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for SubstFolder<'a, 'tcx> {
                 self.ty_for_param(p, t)
             }
             _ => {
-                ty_fold::super_fold_ty(self, t)
+                ty::fold::super_fold_ty(self, t)
             }
         };
 
@@ -731,13 +731,13 @@ impl<'a,'tcx> SubstFolder<'a,'tcx> {
             return ty;
         }
 
-        let result = ty_fold::shift_regions(self.tcx(), self.region_binders_passed, &ty);
+        let result = ty::fold::shift_regions(self.tcx(), self.region_binders_passed, &ty);
         debug!("shift_regions: shifted result = {:?}", result);
 
         result
     }
 
     fn shift_region_through_binders(&self, region: ty::Region) -> ty::Region {
-        ty_fold::shift_region(region, self.region_binders_passed)
+        ty::fold::shift_region(region, self.region_binders_passed)
     }
 }
diff --git a/src/librustc/middle/traits/error_reporting.rs b/src/librustc/middle/traits/error_reporting.rs
index a3a903c3393..5322a571ed9 100644
--- a/src/librustc/middle/traits/error_reporting.rs
+++ b/src/librustc/middle/traits/error_reporting.rs
@@ -27,7 +27,7 @@ use fmt_macros::{Parser, Piece, Position};
 use middle::def_id::DefId;
 use middle::infer::InferCtxt;
 use middle::ty::{self, ToPredicate, HasTypeFlags, ToPolyTraitRef, TraitRef, Ty};
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use std::collections::HashMap;
 use std::fmt;
 use syntax::codemap::Span;
diff --git a/src/librustc/middle/traits/fulfill.rs b/src/librustc/middle/traits/fulfill.rs
index 99e12b7428d..6271dd21166 100644
--- a/src/librustc/middle/traits/fulfill.rs
+++ b/src/librustc/middle/traits/fulfill.rs
@@ -10,7 +10,6 @@
 
 use middle::infer::InferCtxt;
 use middle::ty::{self, RegionEscape, Ty, HasTypeFlags};
-use middle::wf;
 
 use std::fmt;
 use syntax::ast;
@@ -496,8 +495,8 @@ fn process_predicate<'a,'tcx>(selcx: &mut SelectionContext<'a,'tcx>,
                 ObligationCauseCode::RFC1214(_) => true,
                 _ => false,
             };
-            match wf::obligations(selcx.infcx(), obligation.cause.body_id,
-                                  ty, obligation.cause.span, rfc1214) {
+            match ty::wf::obligations(selcx.infcx(), obligation.cause.body_id,
+                                      ty, obligation.cause.span, rfc1214) {
                 Some(obligations) => {
                     new_obligations.extend(obligations);
                     true
diff --git a/src/librustc/middle/traits/mod.rs b/src/librustc/middle/traits/mod.rs
index 667cad8fc88..6c581a701a2 100644
--- a/src/librustc/middle/traits/mod.rs
+++ b/src/librustc/middle/traits/mod.rs
@@ -19,7 +19,7 @@ use middle::def_id::DefId;
 use middle::free_region::FreeRegionMap;
 use middle::subst;
 use middle::ty::{self, HasTypeFlags, Ty};
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use middle::infer::{self, fixup_err_to_string, InferCtxt};
 use std::rc::Rc;
 use syntax::ast;
diff --git a/src/librustc/middle/traits/project.rs b/src/librustc/middle/traits/project.rs
index cacefbb1a85..0d320989cbc 100644
--- a/src/librustc/middle/traits/project.rs
+++ b/src/librustc/middle/traits/project.rs
@@ -24,7 +24,7 @@ use super::util;
 use middle::infer;
 use middle::subst::Subst;
 use middle::ty::{self, ToPredicate, RegionEscape, HasTypeFlags, ToPolyTraitRef, Ty};
-use middle::ty_fold::{self, TypeFoldable, TypeFolder};
+use middle::ty::fold::{TypeFoldable, TypeFolder};
 use syntax::parse::token;
 use util::common::FN_OUTPUT_NAME;
 
@@ -265,7 +265,7 @@ impl<'a,'b,'tcx> TypeFolder<'tcx> for AssociatedTypeNormalizer<'a,'b,'tcx> {
         // normalize it when we instantiate those bound regions (which
         // should occur eventually).
 
-        let ty = ty_fold::super_fold_ty(self, ty);
+        let ty = ty::fold::super_fold_ty(self, ty);
         match ty.sty {
             ty::TyProjection(ref data) if !data.has_escaping_regions() => { // (*)
 
diff --git a/src/librustc/middle/traits/select.rs b/src/librustc/middle/traits/select.rs
index ccdb271d43f..6f422018c13 100644
--- a/src/librustc/middle/traits/select.rs
+++ b/src/librustc/middle/traits/select.rs
@@ -38,15 +38,13 @@ use super::object_safety;
 use super::util;
 
 use middle::def_id::{DefId, LOCAL_CRATE};
-use middle::fast_reject;
-use middle::subst::{Subst, Substs, TypeSpace};
-use middle::ty::{self, ToPredicate, RegionEscape, ToPolyTraitRef, Ty, HasTypeFlags};
 use middle::infer;
 use middle::infer::{InferCtxt, TypeFreshener};
-use middle::ty_fold::TypeFoldable;
-use middle::ty_match;
-use middle::ty_relate::TypeRelation;
-use middle::wf;
+use middle::subst::{Subst, Substs, TypeSpace};
+use middle::ty::{self, ToPredicate, RegionEscape, ToPolyTraitRef, Ty, HasTypeFlags};
+use middle::ty::fast_reject;
+use middle::ty::fold::TypeFoldable;
+use middle::ty::relate::TypeRelation;
 
 use std::cell::RefCell;
 use std::fmt;
@@ -471,9 +469,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             }
 
             ty::Predicate::WellFormed(ty) => {
-                match wf::obligations(self.infcx, obligation.cause.body_id,
-                                      ty, obligation.cause.span,
-                                      obligation.cause.code.is_rfc1214()) {
+                match ty::wf::obligations(self.infcx, obligation.cause.body_id,
+                                          ty, obligation.cause.span,
+                                          obligation.cause.code.is_rfc1214()) {
                     Some(obligations) =>
                         self.evaluate_predicates_recursively(previous_stack, obligations.iter()),
                     None =>
@@ -2824,7 +2822,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                               current: &ty::PolyTraitRef<'tcx>)
                               -> bool
     {
-        let mut matcher = ty_match::Match::new(self.tcx());
+        let mut matcher = ty::_match::Match::new(self.tcx());
         matcher.relate(previous, current).is_ok()
     }
 
diff --git a/src/librustc/middle/ty_match.rs b/src/librustc/middle/ty/_match.rs
index 4aa0e553a7a..2ebb23369bd 100644
--- a/src/librustc/middle/ty_match.rs
+++ b/src/librustc/middle/ty/_match.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use middle::ty::{self, Ty};
-use middle::ty_relate::{self, Relate, TypeRelation, RelateResult};
+use middle::ty::relate::{self, Relate, TypeRelation, RelateResult};
 
 /// A type "A" *matches* "B" if the fresh types in B could be
 /// substituted with values so as to make it equal to A. Matching is
@@ -73,7 +73,7 @@ impl<'a, 'tcx> TypeRelation<'a, 'tcx> for Match<'a, 'tcx> {
 
             (&ty::TyInfer(_), _) |
             (_, &ty::TyInfer(_)) => {
-                Err(ty::TypeError::Sorts(ty_relate::expected_found(self, &a, &b)))
+                Err(ty::TypeError::Sorts(relate::expected_found(self, &a, &b)))
             }
 
             (&ty::TyError, _) | (_, &ty::TyError) => {
@@ -81,7 +81,7 @@ impl<'a, 'tcx> TypeRelation<'a, 'tcx> for Match<'a, 'tcx> {
             }
 
             _ => {
-                ty_relate::super_relate_tys(self, a, b)
+                relate::super_relate_tys(self, a, b)
             }
         }
     }
diff --git a/src/librustc/middle/cast.rs b/src/librustc/middle/ty/cast.rs
index 8cb4f941a22..8cb4f941a22 100644
--- a/src/librustc/middle/cast.rs
+++ b/src/librustc/middle/ty/cast.rs
diff --git a/src/librustc/middle/fast_reject.rs b/src/librustc/middle/ty/fast_reject.rs
index 2b81be19182..2b81be19182 100644
--- a/src/librustc/middle/fast_reject.rs
+++ b/src/librustc/middle/ty/fast_reject.rs
diff --git a/src/librustc/middle/ty_fold.rs b/src/librustc/middle/ty/fold.rs
index c6d213583af..c6d213583af 100644
--- a/src/librustc/middle/ty_fold.rs
+++ b/src/librustc/middle/ty/fold.rs
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty/mod.rs
index 7f61526a8f9..21f068ca887 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty/mod.rs
@@ -43,13 +43,11 @@ use front::map as ast_map;
 use front::map::LinkedPath;
 use metadata::csearch;
 use middle;
-use middle::cast;
 use middle::check_const;
 use middle::const_eval::{self, ConstVal, ErrKind};
 use middle::const_eval::EvalHint::UncheckedExprHint;
 use middle::def::{self, DefMap, ExportMap};
 use middle::def_id::{DefId, LOCAL_CRATE};
-use middle::fast_reject;
 use middle::free_region::FreeRegionMap;
 use middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangItem};
 use middle::region;
@@ -62,8 +60,8 @@ use middle::stability;
 use middle::subst::{self, ParamSpace, Subst, Substs, VecPerParamSpace};
 use middle::traits;
 use middle::ty;
-use middle::ty_fold::{self, TypeFoldable, TypeFolder};
-use middle::ty_walk::{self, TypeWalker};
+use middle::ty::fold::{TypeFoldable, TypeFolder};
+use middle::ty::walk::{TypeWalker};
 use util::common::{memoized, ErrorReported};
 use util::nodemap::{NodeMap, NodeSet, DefIdMap, DefIdSet};
 use util::nodemap::FnvHashMap;
@@ -96,6 +94,15 @@ use rustc_front::hir::{ItemImpl, ItemTrait};
 use rustc_front::hir::{MutImmutable, MutMutable, Visibility};
 use rustc_front::attr::{self, AttrMetaMethods, SignedInt, UnsignedInt};
 
+pub mod cast;
+pub mod fast_reject;
+pub mod fold;
+pub mod _match;
+pub mod outlives;
+pub mod relate;
+pub mod walk;
+pub mod wf;
+
 pub type Disr = u64;
 
 pub const INITIAL_DISCRIMINANT_VALUE: Disr = 0;
@@ -4252,7 +4259,7 @@ impl<'tcx> TyS<'tcx> {
     /// `Foo<Bar<i32>, u32>` yields the sequence `[Bar<i32>, u32]`
     /// (but not `i32`, like `walk`).
     pub fn walk_shallow(&'tcx self) -> IntoIter<Ty<'tcx>> {
-        ty_walk::walk_shallow(self)
+        walk::walk_shallow(self)
     }
 
     pub fn as_opt_param_ty(&self) -> Option<ty::ParamTy> {
@@ -6879,7 +6886,7 @@ impl<'tcx> ctxt<'tcx> {
         -> T
         where T : TypeFoldable<'tcx>
     {
-        ty_fold::replace_late_bound_regions(
+        fold::replace_late_bound_regions(
             self, value,
             |br| ty::ReFree(ty::FreeRegion{scope: all_outlive_scope, bound_region: br})).0
     }
@@ -6891,8 +6898,8 @@ impl<'tcx> ctxt<'tcx> {
         where T: TypeFoldable<'tcx>
     {
         let bound0_value = bound2_value.skip_binder().skip_binder();
-        let value = ty_fold::fold_regions(self, bound0_value, &mut false,
-                                          |region, current_depth| {
+        let value = fold::fold_regions(self, bound0_value, &mut false,
+                                       |region, current_depth| {
             match region {
                 ty::ReLateBound(debruijn, br) if debruijn.depth >= current_depth => {
                     // should be true if no escaping regions from bound2_value
@@ -6922,7 +6929,7 @@ impl<'tcx> ctxt<'tcx> {
     pub fn erase_late_bound_regions<T>(&self, value: &Binder<T>) -> T
         where T : TypeFoldable<'tcx>
     {
-        ty_fold::replace_late_bound_regions(self, value, |_| ty::ReStatic).0
+        fold::replace_late_bound_regions(self, value, |_| ty::ReStatic).0
     }
 
     /// Rewrite any late-bound regions so that they are anonymous.  Region numbers are
@@ -6937,7 +6944,7 @@ impl<'tcx> ctxt<'tcx> {
         where T : TypeFoldable<'tcx>,
     {
         let mut counter = 0;
-        ty::Binder(ty_fold::replace_late_bound_regions(self, sig, |_| {
+        ty::Binder(fold::replace_late_bound_regions(self, sig, |_| {
             counter += 1;
             ReLateBound(ty::DebruijnIndex::new(1), BrAnon(counter))
         }).0)
diff --git a/src/librustc/middle/outlives.rs b/src/librustc/middle/ty/outlives.rs
index 9a2570d710d..9a2570d710d 100644
--- a/src/librustc/middle/outlives.rs
+++ b/src/librustc/middle/ty/outlives.rs
diff --git a/src/librustc/middle/ty_relate/mod.rs b/src/librustc/middle/ty/relate.rs
index d2d612ece6f..7baf075cc69 100644
--- a/src/librustc/middle/ty_relate/mod.rs
+++ b/src/librustc/middle/ty/relate.rs
@@ -16,7 +16,7 @@
 use middle::def_id::DefId;
 use middle::subst::{ErasedRegions, NonerasedRegions, ParamSpace, Substs};
 use middle::ty::{self, HasTypeFlags, Ty, TypeError};
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use std::rc::Rc;
 use syntax::abi;
 use rustc_front::hir as ast;
diff --git a/src/librustc/middle/ty_walk.rs b/src/librustc/middle/ty/walk.rs
index 81cad448690..81cad448690 100644
--- a/src/librustc/middle/ty_walk.rs
+++ b/src/librustc/middle/ty/walk.rs
diff --git a/src/librustc/middle/wf.rs b/src/librustc/middle/ty/wf.rs
index 96942756b98..20534f72666 100644
--- a/src/librustc/middle/wf.rs
+++ b/src/librustc/middle/ty/wf.rs
@@ -10,7 +10,7 @@
 
 use middle::def_id::DefId;
 use middle::infer::InferCtxt;
-use middle::outlives::{self, Component};
+use middle::ty::outlives::{self, Component};
 use middle::subst::Substs;
 use middle::traits;
 use middle::ty::{self, RegionEscape, ToPredicate, Ty};
@@ -544,4 +544,3 @@ pub fn object_region_bounds<'tcx>(
 
     tcx.required_region_bounds(open_ty, predicates)
 }
-
diff --git a/src/librustc/util/ppaux.rs b/src/librustc/util/ppaux.rs
index a0701d852bc..222de426432 100644
--- a/src/librustc/util/ppaux.rs
+++ b/src/librustc/util/ppaux.rs
@@ -21,7 +21,7 @@ use middle::ty::{TyParam, TyRawPtr, TyRef, TyTuple};
 use middle::ty::TyClosure;
 use middle::ty::{TyBox, TyTrait, TyInt, TyUint, TyInfer};
 use middle::ty::{self, TypeAndMut, Ty, HasTypeFlags};
-use middle::ty_fold::{self, TypeFoldable};
+use middle::ty::fold::{self, TypeFoldable};
 
 use std::fmt;
 use syntax::abi;
@@ -219,7 +219,7 @@ fn in_binder<'tcx, T, U>(f: &mut fmt::Formatter,
         }
     };
 
-    let new_value = ty_fold::replace_late_bound_regions(tcx, &value, |br| {
+    let new_value = fold::replace_late_bound_regions(tcx, &value, |br| {
         let _ = start_or_continue(f, "for<", ", ");
         ty::ReLateBound(ty::DebruijnIndex::new(1), match br {
             ty::BrNamed(_, name) => {
@@ -255,7 +255,7 @@ fn in_binder<'tcx, T, U>(f: &mut fmt::Formatter,
 struct TraitAndProjections<'tcx>(ty::TraitRef<'tcx>, Vec<ty::ProjectionPredicate<'tcx>>);
 
 impl<'tcx> TypeFoldable<'tcx> for TraitAndProjections<'tcx> {
-    fn fold_with<F:ty_fold::TypeFolder<'tcx>>(&self, folder: &mut F)
+    fn fold_with<F: fold::TypeFolder<'tcx>>(&self, folder: &mut F)
                                               -> TraitAndProjections<'tcx> {
         TraitAndProjections(self.0.fold_with(folder), self.1.fold_with(folder))
     }
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index c96495fcfc9..96d9572b485 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -24,7 +24,7 @@ use rustc_typeck::middle::stability;
 use rustc_typeck::middle::subst;
 use rustc_typeck::middle::subst::Subst;
 use rustc_typeck::middle::ty::{self, Ty, RegionEscape};
-use rustc_typeck::middle::ty_relate::TypeRelation;
+use rustc_typeck::middle::ty::relate::TypeRelation;
 use rustc_typeck::middle::infer;
 use rustc_typeck::middle::infer::lub::Lub;
 use rustc_typeck::middle::infer::glb::Glb;
diff --git a/src/librustc_trans/trans/common.rs b/src/librustc_trans/trans/common.rs
index 6843e4cab83..044e96db04d 100644
--- a/src/librustc_trans/trans/common.rs
+++ b/src/librustc_trans/trans/common.rs
@@ -38,8 +38,7 @@ use trans::type_::Type;
 use trans::type_of;
 use middle::traits;
 use middle::ty::{self, HasTypeFlags, Ty};
-use middle::ty_fold;
-use middle::ty_fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
 use rustc::front::map::{PathElem, PathName};
 use rustc_front::hir;
 use util::nodemap::{FnvHashMap, NodeMap};
@@ -60,7 +59,7 @@ pub use trans::context::CrateContext;
 /// Returns an equivalent value with all free regions removed (note
 /// that late-bound regions remain, because they are important for
 /// subtyping, but they are anonymized and normalized as well). This
-/// is a stronger, caching version of `ty_fold::erase_regions`.
+/// is a stronger, caching version of `ty::fold::erase_regions`.
 pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
     where T : TypeFoldable<'tcx>
 {
@@ -80,7 +79,7 @@ pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
                 Some(u) => return u
             }
 
-            let t_norm = ty_fold::super_fold_ty(self, ty);
+            let t_norm = ty::fold::super_fold_ty(self, ty);
             self.tcx().normalized_cache.borrow_mut().insert(ty, t_norm);
             return t_norm;
         }
@@ -89,7 +88,7 @@ pub fn erase_regions<'tcx,T>(cx: &ty::ctxt<'tcx>, value: &T) -> T
             where T : TypeFoldable<'tcx>
         {
             let u = self.tcx().anonymize_late_bound_regions(t);
-            ty_fold::super_fold_binder(self, &u)
+            ty::fold::super_fold_binder(self, &u)
         }
 
         fn fold_region(&mut self, r: ty::Region) -> ty::Region {
diff --git a/src/librustc_trans/trans/consts.rs b/src/librustc_trans/trans/consts.rs
index a3ba174a6e5..c98760ce02a 100644
--- a/src/librustc_trans/trans/consts.rs
+++ b/src/librustc_trans/trans/consts.rs
@@ -33,9 +33,9 @@ use trans::declare;
 use trans::monomorphize;
 use trans::type_::Type;
 use trans::type_of;
-use middle::cast::{CastTy,IntTy};
 use middle::subst::Substs;
 use middle::ty::{self, Ty};
+use middle::ty::cast::{CastTy,IntTy};
 use util::nodemap::NodeMap;
 
 use rustc_front::hir;
diff --git a/src/librustc_trans/trans/expr.rs b/src/librustc_trans/trans/expr.rs
index 3a7fa040e4f..59040b9cafe 100644
--- a/src/librustc_trans/trans/expr.rs
+++ b/src/librustc_trans/trans/expr.rs
@@ -71,10 +71,10 @@ use trans::machine;
 use trans::meth;
 use trans::tvec;
 use trans::type_of;
-use middle::cast::{CastKind, CastTy};
 use middle::ty::{AdjustDerefRef, AdjustReifyFnPointer, AdjustUnsafeFnPointer};
 use middle::ty::{self, Ty};
 use middle::ty::MethodCall;
+use middle::ty::cast::{CastKind, CastTy};
 use util::common::indenter;
 use trans::machine::{llsize_of, llsize_of_alloc};
 use trans::type_::Type;
@@ -2045,8 +2045,8 @@ fn trans_imm_cast<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
                               id: ast::NodeId)
                               -> DatumBlock<'blk, 'tcx, Expr>
 {
-    use middle::cast::CastTy::*;
-    use middle::cast::IntTy::*;
+    use middle::ty::cast::CastTy::*;
+    use middle::ty::cast::IntTy::*;
 
     fn int_cast(bcx: Block,
                 lldsttype: Type,
diff --git a/src/librustc_trans/trans/monomorphize.rs b/src/librustc_trans/trans/monomorphize.rs
index ae425f29132..1ef9981a0a4 100644
--- a/src/librustc_trans/trans/monomorphize.rs
+++ b/src/librustc_trans/trans/monomorphize.rs
@@ -17,7 +17,7 @@ use middle::infer;
 use middle::subst;
 use middle::subst::{Subst, Substs};
 use middle::traits;
-use middle::ty_fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
 use trans::attributes;
 use trans::base::{trans_enum_variant, push_ctxt, get_item_val};
 use trans::base::trans_fn;
diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs
index fb61f1ef42d..e6f9b1f9d6d 100644
--- a/src/librustc_typeck/astconv.rs
+++ b/src/librustc_typeck/astconv.rs
@@ -53,13 +53,12 @@ use middle::const_eval::{self, ConstVal};
 use middle::const_eval::EvalHint::UncheckedExprHint;
 use middle::def;
 use middle::def_id::{DefId, LOCAL_CRATE};
-use middle::wf::object_region_bounds;
 use middle::resolve_lifetime as rl;
 use middle::privacy::{AllPublic, LastMod};
 use middle::subst::{FnSpace, TypeSpace, SelfSpace, Subst, Substs, ParamSpace};
 use middle::traits;
 use middle::ty::{self, RegionEscape, Ty, ToPredicate, HasTypeFlags};
-use middle::ty_fold;
+use middle::ty::wf::object_region_bounds;
 use require_c_abi_if_variadic;
 use rscope::{self, UnelidableRscope, RegionScope, ElidableRscope,
              ObjectLifetimeDefaultRscope, ShiftedRscope, BindingRscope,
@@ -535,9 +534,9 @@ fn find_implied_output_region<'tcx>(tcx: &ty::ctxt<'tcx>,
 
     for (input_type, input_pat) in input_tys.iter().zip(input_pats) {
         let mut regions = FnvHashSet();
-        let have_bound_regions = ty_fold::collect_regions(tcx,
-                                                          input_type,
-                                                          &mut regions);
+        let have_bound_regions = ty::fold::collect_regions(tcx,
+                                                           input_type,
+                                                           &mut regions);
 
         debug!("find_implied_output_regions: collected {:?} from {:?} \
                 have_bound_regions={:?}", &regions, input_type, have_bound_regions);
@@ -2249,7 +2248,7 @@ impl<'tcx> Bounds<'tcx> {
         for &region_bound in &self.region_bounds {
             // account for the binder being introduced below; no need to shift `param_ty`
             // because, at present at least, it can only refer to early-bound regions
-            let region_bound = ty_fold::shift_region(region_bound, 1);
+            let region_bound = ty::fold::shift_region(region_bound, 1);
             vec.push(ty::Binder(ty::OutlivesPredicate(param_ty, region_bound)).to_predicate());
         }
 
diff --git a/src/librustc_typeck/check/assoc.rs b/src/librustc_typeck/check/assoc.rs
index c80c48a9692..8dc95562e44 100644
--- a/src/librustc_typeck/check/assoc.rs
+++ b/src/librustc_typeck/check/assoc.rs
@@ -12,7 +12,7 @@ use middle::infer::InferCtxt;
 use middle::traits::{self, FulfillmentContext, Normalized, MiscObligation,
                      SelectionContext, ObligationCause};
 use middle::ty::HasTypeFlags;
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use syntax::ast;
 use syntax::codemap::Span;
 
diff --git a/src/librustc_typeck/check/cast.rs b/src/librustc_typeck/check/cast.rs
index 799a3e86a75..98c8c0a3199 100644
--- a/src/librustc_typeck/check/cast.rs
+++ b/src/librustc_typeck/check/cast.rs
@@ -44,9 +44,9 @@ use super::FnCtxt;
 use super::structurally_resolved_type;
 
 use lint;
-use middle::cast::{CastKind, CastTy};
 use middle::def_id::DefId;
 use middle::ty::{self, Ty, HasTypeFlags};
+use middle::ty::cast::{CastKind, CastTy};
 use syntax::codemap::Span;
 use rustc_front::hir;
 use rustc_front::hir::UintTy::TyU8;
@@ -226,8 +226,8 @@ impl<'tcx> CastCheck<'tcx> {
     /// can return Ok and create type errors in the fcx rather than returning
     /// directly. coercion-cast is handled in check instead of here.
     fn do_check<'a>(&self, fcx: &FnCtxt<'a, 'tcx>) -> Result<CastKind, CastError> {
-        use middle::cast::IntTy::*;
-        use middle::cast::CastTy::*;
+        use middle::ty::cast::IntTy::*;
+        use middle::ty::cast::CastTy::*;
 
         let (t_from, t_cast) = match (CastTy::from_ty(self.expr_ty),
                                       CastTy::from_ty(self.cast_ty)) {
diff --git a/src/librustc_typeck/check/coercion.rs b/src/librustc_typeck/check/coercion.rs
index 65409afa52d..d3a292676c5 100644
--- a/src/librustc_typeck/check/coercion.rs
+++ b/src/librustc_typeck/check/coercion.rs
@@ -67,7 +67,7 @@ use middle::traits::{self, ObligationCause};
 use middle::traits::{predicate_for_trait_def, report_selection_error};
 use middle::ty::{AutoDerefRef, AdjustDerefRef};
 use middle::ty::{self, LvaluePreference, TypeAndMut, Ty, TypeError};
-use middle::ty_relate::RelateResult;
+use middle::ty::relate::RelateResult;
 use util::common::indent;
 
 use std::cell::RefCell;
diff --git a/src/librustc_typeck/check/intrinsic.rs b/src/librustc_typeck/check/intrinsic.rs
index d1f898d82fd..e7c7b5831d0 100644
--- a/src/librustc_typeck/check/intrinsic.rs
+++ b/src/librustc_typeck/check/intrinsic.rs
@@ -17,7 +17,7 @@ use middle::def_id::DefId;
 use middle::subst;
 use middle::ty::FnSig;
 use middle::ty::{self, Ty};
-use middle::ty_fold::TypeFolder;
+use middle::ty::fold::TypeFolder;
 use {CrateCtxt, require_same_types};
 
 use std::collections::{HashMap};
diff --git a/src/librustc_typeck/check/method/confirm.rs b/src/librustc_typeck/check/method/confirm.rs
index 040e644a94d..048a2b62bca 100644
--- a/src/librustc_typeck/check/method/confirm.rs
+++ b/src/librustc_typeck/check/method/confirm.rs
@@ -16,7 +16,7 @@ use middle::def_id::DefId;
 use middle::subst::{self};
 use middle::traits;
 use middle::ty::{self, NoPreference, PreferMutLvalue, Ty};
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use middle::infer;
 use middle::infer::InferCtxt;
 use syntax::codemap::Span;
diff --git a/src/librustc_typeck/check/method/probe.rs b/src/librustc_typeck/check/method/probe.rs
index b04899f5ecd..f65602d9aac 100644
--- a/src/librustc_typeck/check/method/probe.rs
+++ b/src/librustc_typeck/check/method/probe.rs
@@ -16,13 +16,12 @@ use super::suggest;
 use check;
 use check::{FnCtxt, UnresolvedTypeAction};
 use middle::def_id::DefId;
-use middle::fast_reject;
 use middle::subst;
 use middle::subst::Subst;
 use middle::traits;
 use middle::ty::{self, NoPreference, RegionEscape, Ty, ToPolyTraitRef, TraitRef};
 use middle::ty::HasTypeFlags;
-use middle::ty_fold::TypeFoldable;
+use middle::ty::fold::TypeFoldable;
 use middle::infer;
 use middle::infer::InferCtxt;
 use syntax::ast;
@@ -41,7 +40,7 @@ struct ProbeContext<'a, 'tcx:'a> {
     mode: Mode,
     item_name: ast::Name,
     steps: Rc<Vec<CandidateStep<'tcx>>>,
-    opt_simplified_steps: Option<Vec<fast_reject::SimplifiedType>>,
+    opt_simplified_steps: Option<Vec<ty::fast_reject::SimplifiedType>>,
     inherent_candidates: Vec<Candidate<'tcx>>,
     extension_candidates: Vec<Candidate<'tcx>>,
     impl_dups: HashSet<DefId>,
@@ -163,7 +162,7 @@ pub fn probe<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>,
     // Create a list of simplified self types, if we can.
     let mut simplified_steps = Vec::new();
     for step in &steps {
-        match fast_reject::simplify_type(fcx.tcx(), step.self_ty, true) {
+        match ty::fast_reject::simplify_type(fcx.tcx(), step.self_ty, true) {
             None => { break; }
             Some(simplified_type) => { simplified_steps.push(simplified_type); }
         }
@@ -236,7 +235,7 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
            mode: Mode,
            item_name: ast::Name,
            steps: Vec<CandidateStep<'tcx>>,
-           opt_simplified_steps: Option<Vec<fast_reject::SimplifiedType>>)
+           opt_simplified_steps: Option<Vec<ty::fast_reject::SimplifiedType>>)
            -> ProbeContext<'a,'tcx>
     {
         ProbeContext {
@@ -684,7 +683,7 @@ impl<'a,'tcx> ProbeContext<'a,'tcx> {
 
         let impl_type = self.tcx().lookup_item_type(impl_def_id);
         let impl_simplified_type =
-            match fast_reject::simplify_type(self.tcx(), impl_type.ty, false) {
+            match ty::fast_reject::simplify_type(self.tcx(), impl_type.ty, false) {
                 Some(simplified_type) => simplified_type,
                 None => { return true; }
             };
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index b1fbf97d1a7..dc433786ae4 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -97,7 +97,7 @@ use middle::ty::{Disr, ParamTy, ParameterEnvironment};
 use middle::ty::{LvaluePreference, NoPreference, PreferMutLvalue};
 use middle::ty::{self, HasTypeFlags, RegionEscape, ToPolyTraitRef, Ty};
 use middle::ty::{MethodCall, MethodCallee};
-use middle::ty_fold::{TypeFolder, TypeFoldable};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
 use require_c_abi_if_variadic;
 use rscope::{ElisionFailureInfo, RegionScope};
 use session::Session;
diff --git a/src/librustc_typeck/check/regionck.rs b/src/librustc_typeck/check/regionck.rs
index 844e143b9fa..b6ff7b529c5 100644
--- a/src/librustc_typeck/check/regionck.rs
+++ b/src/librustc_typeck/check/regionck.rs
@@ -88,14 +88,13 @@ use check::FnCtxt;
 use middle::free_region::FreeRegionMap;
 use middle::implicator::{self, Implication};
 use middle::mem_categorization as mc;
-use middle::outlives;
 use middle::region::CodeExtent;
 use middle::subst::Substs;
 use middle::traits;
 use middle::ty::{self, RegionEscape, ReScope, Ty, MethodCall, HasTypeFlags};
 use middle::infer::{self, GenericKind, InferCtxt, SubregionOrigin, VerifyBound};
 use middle::pat_util;
-use middle::wf::{self, ImpliedBound};
+use middle::ty::wf::ImpliedBound;
 
 use std::mem;
 use std::rc::Rc;
@@ -420,7 +419,7 @@ impl<'a, 'tcx> Rcx<'a, 'tcx> {
         for &ty in fn_sig_tys {
             let ty = self.resolve_type(ty);
             debug!("relate_free_regions(t={:?})", ty);
-            let implied_bounds = wf::implied_bounds(self.fcx.infcx(), body_id, ty, span);
+            let implied_bounds = ty::wf::implied_bounds(self.fcx.infcx(), body_id, ty, span);
 
             // Record any relations between free regions that we observe into the free-region-map.
             self.free_region_map.relate_free_regions_from_implied_bounds(&implied_bounds);
@@ -1527,31 +1526,31 @@ pub fn type_must_outlive<'a, 'tcx>(rcx: &Rcx<'a, 'tcx>,
 
     assert!(!ty.has_escaping_regions());
 
-    let components = outlives::components(rcx.infcx(), ty);
+    let components = ty::outlives::components(rcx.infcx(), ty);
     components_must_outlive(rcx, origin, components, region);
 }
 
 fn components_must_outlive<'a, 'tcx>(rcx: &Rcx<'a, 'tcx>,
                                      origin: infer::SubregionOrigin<'tcx>,
-                                     components: Vec<outlives::Component<'tcx>>,
+                                     components: Vec<ty::outlives::Component<'tcx>>,
                                      region: ty::Region)
 {
     for component in components {
         let origin = origin.clone();
         match component {
-            outlives::Component::Region(region1) => {
+            ty::outlives::Component::Region(region1) => {
                 rcx.fcx.mk_subr(origin, region, region1);
             }
-            outlives::Component::Param(param_ty) => {
+            ty::outlives::Component::Param(param_ty) => {
                 param_ty_must_outlive(rcx, origin, region, param_ty);
             }
-            outlives::Component::Projection(projection_ty) => {
+            ty::outlives::Component::Projection(projection_ty) => {
                 projection_must_outlive(rcx, origin, region, projection_ty);
             }
-            outlives::Component::EscapingProjection(subcomponents) => {
+            ty::outlives::Component::EscapingProjection(subcomponents) => {
                 components_must_outlive(rcx, origin, subcomponents, region);
             }
-            outlives::Component::UnresolvedInferenceVariable(v) => {
+            ty::outlives::Component::UnresolvedInferenceVariable(v) => {
                 // ignore this, we presume it will yield an error
                 // later, since if a type variable is not resolved by
                 // this point it never will be
@@ -1559,7 +1558,7 @@ fn components_must_outlive<'a, 'tcx>(rcx: &Rcx<'a, 'tcx>,
                     origin.span(),
                     &format!("unresolved inference variable in outlives: {:?}", v));
             }
-            outlives::Component::RFC1214(subcomponents) => {
+            ty::outlives::Component::RFC1214(subcomponents) => {
                 let suborigin = infer::RFC1214Subregion(Rc::new(origin));
                 components_must_outlive(rcx, suborigin, subcomponents, region);
             }
diff --git a/src/librustc_typeck/check/wf.rs b/src/librustc_typeck/check/wf.rs
index 99cb1281307..2c931e7830d 100644
--- a/src/librustc_typeck/check/wf.rs
+++ b/src/librustc_typeck/check/wf.rs
@@ -17,7 +17,7 @@ use middle::region;
 use middle::subst::{self, TypeSpace, FnSpace, ParamSpace, SelfSpace};
 use middle::traits;
 use middle::ty::{self, Ty};
-use middle::ty_fold::{TypeFolder, TypeFoldable, super_fold_ty};
+use middle::ty::fold::{TypeFolder, TypeFoldable, super_fold_ty};
 
 use std::cell::RefCell;
 use std::collections::HashSet;
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index a53f15ce2aa..06dd80c57ad 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -16,8 +16,7 @@ use middle::def_id::DefId;
 use middle::subst::{self, TypeSpace, FnSpace, ParamSpace, SelfSpace};
 use middle::traits;
 use middle::ty::{self, Ty};
-use middle::ty_fold::{TypeFolder};
-use middle::wf;
+use middle::ty::fold::{TypeFolder};
 
 use std::cell::RefCell;
 use std::collections::HashSet;
@@ -309,11 +308,11 @@ impl<'ccx, 'tcx> CheckTypeWellFormedVisitor<'ccx, 'tcx> {
                         fcx.instantiate_type_scheme(
                             ast_trait_ref.path.span, free_substs, &trait_ref);
                     let obligations =
-                        wf::trait_obligations(fcx.infcx(),
-                                              fcx.body_id,
-                                              &trait_ref,
-                                              ast_trait_ref.path.span,
-                                              true);
+                        ty::wf::trait_obligations(fcx.infcx(),
+                                                  fcx.body_id,
+                                                  &trait_ref,
+                                                  ast_trait_ref.path.span,
+                                                  true);
                     for obligation in obligations {
                         fcx.register_predicate(obligation);
                     }
@@ -341,11 +340,11 @@ impl<'ccx, 'tcx> CheckTypeWellFormedVisitor<'ccx, 'tcx> {
         let obligations =
             predicates.predicates
                       .iter()
-                      .flat_map(|p| wf::predicate_obligations(fcx.infcx(),
-                                                              fcx.body_id,
-                                                              p,
-                                                              span,
-                                                              true));
+                      .flat_map(|p| ty::wf::predicate_obligations(fcx.infcx(),
+                                                                  fcx.body_id,
+                                                                  p,
+                                                                  span,
+                                                                  true));
 
         for obligation in obligations {
             fcx.register_predicate(obligation);
diff --git a/src/librustc_typeck/check/writeback.rs b/src/librustc_typeck/check/writeback.rs
index 94c01eb70e8..de841a0cc00 100644
--- a/src/librustc_typeck/check/writeback.rs
+++ b/src/librustc_typeck/check/writeback.rs
@@ -18,7 +18,7 @@ use check::FnCtxt;
 use middle::def_id::DefId;
 use middle::pat_util;
 use middle::ty::{self, Ty, MethodCall, MethodCallee};
-use middle::ty_fold::{TypeFolder,TypeFoldable};
+use middle::ty::fold::{TypeFolder,TypeFoldable};
 use middle::infer;
 use write_substs_to_tcx;
 use write_ty_to_tcx;
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index f0b68e5e902..930eb431f49 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -78,7 +78,7 @@ use middle::subst::{Substs, FnSpace, ParamSpace, SelfSpace, TypeSpace, VecPerPar
 use middle::ty::{ToPredicate, ImplContainer, ImplOrTraitItemContainer, TraitContainer};
 use middle::ty::{self, RegionEscape, ToPolyTraitRef, Ty, TypeScheme, IntTypeExt};
 use middle::ty::{VariantKind};
-use middle::ty_fold::{self, TypeFolder, TypeFoldable};
+use middle::ty::fold::{TypeFolder, TypeFoldable};
 use middle::infer;
 use rscope::*;
 use rustc::front::map as hir_map;
@@ -2374,7 +2374,7 @@ fn check_method_self_type<'a, 'tcx, RS:RegionScope>(
          * before we really have a `ParameterEnvironment` to check.
          */
 
-        ty_fold::fold_regions(tcx, value, &mut false, |region, _| {
+        ty::fold::fold_regions(tcx, value, &mut false, |region, _| {
             match region {
                 ty::ReEarlyBound(data) => {
                     let def_id = DefId::local(data.param_id);
diff --git a/src/librustc_typeck/rscope.rs b/src/librustc_typeck/rscope.rs
index 28403ab2282..1b02c736dce 100644
--- a/src/librustc_typeck/rscope.rs
+++ b/src/librustc_typeck/rscope.rs
@@ -10,7 +10,6 @@
 
 
 use middle::ty;
-use middle::ty_fold;
 
 use std::cell::Cell;
 use syntax::codemap::Span;
@@ -239,11 +238,11 @@ impl<'r> ShiftedRscope<'r> {
 impl<'r> RegionScope for ShiftedRscope<'r> {
     fn object_lifetime_default(&self, span: Span) -> Option<ty::Region> {
         self.base_scope.object_lifetime_default(span)
-            .map(|r| ty_fold::shift_region(r, 1))
+            .map(|r| ty::fold::shift_region(r, 1))
     }
 
     fn base_object_lifetime_default(&self, span: Span) -> ty::Region {
-        ty_fold::shift_region(self.base_scope.base_object_lifetime_default(span), 1)
+        ty::fold::shift_region(self.base_scope.base_object_lifetime_default(span), 1)
     }
 
     fn anon_regions(&self,
@@ -254,7 +253,7 @@ impl<'r> RegionScope for ShiftedRscope<'r> {
         match self.base_scope.anon_regions(span, count) {
             Ok(mut v) => {
                 for r in &mut v {
-                    *r = ty_fold::shift_region(*r, 1);
+                    *r = ty::fold::shift_region(*r, 1);
                 }
                 Ok(v)
             }