1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
12 * Conversion from AST representation of types to the ty.rs
13 * representation. The main routine here is `ast_ty_to_ty()`: each use
14 * is parameterized by an instance of `AstConv` and a `RegionScope`.
16 * The parameterization of `ast_ty_to_ty()` is because it behaves
17 * somewhat differently during the collect and check phases,
18 * particularly with respect to looking up the types of top-level
19 * items. In the collect phase, the crate context is used as the
20 * `AstConv` instance; in this phase, the `get_item_ty()` function
21 * triggers a recursive call to `ty_of_item()` (note that
22 * `ast_ty_to_ty()` will detect recursive types and report an error).
23 * In the check phase, when the FnCtxt is used as the `AstConv`,
24 * `get_item_ty()` just looks up the item type in `tcx.tcache`.
26 * The `RegionScope` trait controls what happens when the user does
27 * not specify a region in some location where a region is required
28 * (e.g., if the user writes `&Foo` as a type rather than `&'a Foo`).
29 * See the `rscope` module for more details.
31 * Unlike the `AstConv` trait, the region scope can change as we descend
32 * the type. This is to accommodate the fact that (a) fn types are binding
33 * scopes and (b) the default region may change. To understand case (a),
34 * consider something like:
36 * type foo = { x: &a.int, y: |&a.int| }
38 * The type of `x` is an error because there is no region `a` in scope.
39 * In the type of `y`, however, region `a` is considered a bound region
40 * as it does not already appear in scope.
42 * Case (b) says that if you have a type:
44 * type bar = fn(&foo, &a.foo)
45 * The fully expanded version of type bar is:
46 * type bar = fn(&'foo &, &a.foo<'a>)
47 * Note that the self region for the `foo` defaulted to `&` in the first
48 * case but `&a` in the second. Basically, defaults that appear inside
49 * an rptr (`&r.T`) use the region `r` that appears in the rptr.
52 use middle::const_eval;
54 use middle::lang_items::FnMutTraitLangItem;
55 use rl = middle::resolve_lifetime;
56 use middle::subst::{FnSpace, TypeSpace, SelfSpace, Subst, Substs};
58 use middle::typeck::TypeAndSubsts;
59 use middle::typeck::lookup_def_tcx;
60 use middle::typeck::rscope::RegionScope;
61 use middle::typeck::rscope;
62 use util::ppaux::Repr;
66 use syntax::{ast, ast_util};
67 use syntax::codemap::Span;
68 use syntax::owned_slice::OwnedSlice;
69 use syntax::print::pprust::{lifetime_to_str, path_to_str};
72 fn tcx<'a>(&'a self) -> &'a ty::ctxt;
73 fn get_item_ty(&self, id: ast::DefId) -> ty::Polytype;
74 fn get_trait_def(&self, id: ast::DefId) -> Rc<ty::TraitDef>;
76 // what type should we use when a type is omitted?
77 fn ty_infer(&self, span: Span) -> ty::t;
80 pub fn ast_region_to_region(tcx: &ty::ctxt, lifetime: &ast::Lifetime)
82 let r = match tcx.named_region_map.find(&lifetime.id) {
84 // should have been recorded by the `resolve_lifetime` pass
85 tcx.sess.span_bug(lifetime.span, "unresolved lifetime");
88 Some(&rl::DefStaticRegion) => {
92 Some(&rl::DefLateBoundRegion(binder_id, _, id)) => {
93 ty::ReLateBound(binder_id, ty::BrNamed(ast_util::local_def(id),
97 Some(&rl::DefEarlyBoundRegion(space, index, id)) => {
98 ty::ReEarlyBound(id, space, index, lifetime.name)
101 Some(&rl::DefFreeRegion(scope_id, id)) => {
102 ty::ReFree(ty::FreeRegion {
104 bound_region: ty::BrNamed(ast_util::local_def(id),
110 debug!("ast_region_to_region(lifetime={} id={}) yields {}",
111 lifetime_to_str(lifetime),
112 lifetime.id, r.repr(tcx));
117 pub fn opt_ast_region_to_region<AC:AstConv,RS:RegionScope>(
121 opt_lifetime: &Option<ast::Lifetime>) -> ty::Region
123 let r = match *opt_lifetime {
124 Some(ref lifetime) => {
125 ast_region_to_region(this.tcx(), lifetime)
129 match rscope.anon_regions(default_span, 1) {
131 debug!("optional region in illegal location");
132 this.tcx().sess.span_err(
133 default_span, "missing lifetime specifier");
144 debug!("opt_ast_region_to_region(opt_lifetime={:?}) yields {}",
145 opt_lifetime.as_ref().map(|e| lifetime_to_str(e)),
151 fn ast_path_substs<AC:AstConv,RS:RegionScope>(
154 decl_generics: &ty::Generics,
155 self_ty: Option<ty::t>,
156 path: &ast::Path) -> Substs
159 * Given a path `path` that refers to an item `I` with the
160 * declared generics `decl_generics`, returns an appropriate
161 * set of substitutions for this particular reference to `I`.
164 let tcx = this.tcx();
166 // ast_path_substs() is only called to convert paths that are
167 // known to refer to traits, types, or structs. In these cases,
168 // all type parameters defined for the item being referenced will
169 // be in the TypeSpace or SelfSpace.
171 // Note: in the case of traits, the self parameter is also
172 // defined, but we don't currently create a `type_param_def` for
173 // `Self` because it is implicit.
174 assert!(decl_generics.regions.all(|d| d.space == TypeSpace));
175 assert!(decl_generics.types.all(|d| d.space != FnSpace));
177 // If the type is parameterized by the this region, then replace this
178 // region with the current anon region binding (in other words,
179 // whatever & would get replaced with).
180 let expected_num_region_params = decl_generics.regions.len(TypeSpace);
181 let supplied_num_region_params = path.segments.last().unwrap().lifetimes.len();
182 let regions = if expected_num_region_params == supplied_num_region_params {
183 path.segments.last().unwrap().lifetimes.iter().map(
184 |l| ast_region_to_region(this.tcx(), l)).collect::<Vec<_>>()
187 rscope.anon_regions(path.span, expected_num_region_params);
189 if supplied_num_region_params != 0 || anon_regions.is_err() {
192 format!("wrong number of lifetime parameters: \
193 expected {} but found {}",
194 expected_num_region_params,
195 supplied_num_region_params).as_slice());
199 Ok(v) => v.move_iter().collect(),
200 Err(()) => Vec::from_fn(expected_num_region_params,
201 |_| ty::ReStatic) // hokey
205 // Convert the type parameters supplied by the user.
206 let ty_param_defs = decl_generics.types.get_vec(TypeSpace);
207 let supplied_ty_param_count = path.segments.iter().flat_map(|s| s.types.iter()).count();
208 let formal_ty_param_count = ty_param_defs.len();
209 let required_ty_param_count = ty_param_defs.iter()
210 .take_while(|x| x.default.is_none())
212 if supplied_ty_param_count < required_ty_param_count {
213 let expected = if required_ty_param_count < formal_ty_param_count {
218 this.tcx().sess.span_fatal(path.span,
219 format!("wrong number of type arguments: {} {} but found {}",
221 required_ty_param_count,
222 supplied_ty_param_count).as_slice());
223 } else if supplied_ty_param_count > formal_ty_param_count {
224 let expected = if required_ty_param_count < formal_ty_param_count {
229 this.tcx().sess.span_fatal(path.span,
230 format!("wrong number of type arguments: {} {} but found {}",
232 formal_ty_param_count,
233 supplied_ty_param_count).as_slice());
236 if supplied_ty_param_count > required_ty_param_count
237 && !this.tcx().sess.features.default_type_params.get() {
238 this.tcx().sess.span_err(path.span, "default type parameters are \
239 experimental and possibly buggy");
240 this.tcx().sess.span_note(path.span, "add #![feature(default_type_params)] \
241 to the crate attributes to enable");
244 let tps = path.segments.iter().flat_map(|s| s.types.iter())
245 .map(|a_t| ast_ty_to_ty(this, rscope, &**a_t))
248 let mut substs = Substs::new_type(tps, regions);
252 // If no self-type is provided, it's still possible that
253 // one was declared, because this could be an object type.
256 // If a self-type is provided, one should have been
257 // "declared" (in other words, this should be a
259 assert!(decl_generics.types.get_self().is_some());
260 substs.types.push(SelfSpace, ty);
264 for param in ty_param_defs.slice_from(supplied_ty_param_count).iter() {
265 let default = param.default.unwrap();
266 let default = default.subst_spanned(tcx, &substs, Some(path.span));
267 substs.types.push(TypeSpace, default);
273 pub fn ast_path_to_trait_ref<AC:AstConv,RS:RegionScope>(
276 trait_def_id: ast::DefId,
277 self_ty: Option<ty::t>,
278 path: &ast::Path) -> Rc<ty::TraitRef> {
279 let trait_def = this.get_trait_def(trait_def_id);
280 Rc::new(ty::TraitRef {
281 def_id: trait_def_id,
282 substs: ast_path_substs(this, rscope, &trait_def.generics, self_ty, path)
286 pub fn ast_path_to_ty<AC:AstConv,RS:RegionScope>(
293 let tcx = this.tcx();
297 } = this.get_item_ty(did);
299 let substs = ast_path_substs(this, rscope, &generics, None, path);
300 let ty = decl_ty.subst(tcx, &substs);
301 TypeAndSubsts { substs: substs, ty: ty }
304 pub static NO_REGIONS: uint = 1;
305 pub static NO_TPS: uint = 2;
307 fn check_path_args(tcx: &ty::ctxt,
310 if (flags & NO_TPS) != 0u {
311 if !path.segments.iter().all(|s| s.types.is_empty()) {
314 "type parameters are not allowed on this type");
318 if (flags & NO_REGIONS) != 0u {
319 if !path.segments.last().unwrap().lifetimes.is_empty() {
322 "region parameters are not allowed on this type");
327 pub fn ast_ty_to_prim_ty(tcx: &ty::ctxt, ast_ty: &ast::Ty) -> Option<ty::t> {
329 ast::TyPath(ref path, _, id) => {
330 let a_def = match tcx.def_map.borrow().find(&id) {
332 tcx.sess.span_bug(ast_ty.span,
333 format!("unbound path {}",
334 path_to_str(path)).as_slice())
339 def::DefPrimTy(nty) => {
342 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
346 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
350 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
351 Some(ty::mk_mach_int(it))
353 ast::TyUint(uit) => {
354 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
355 Some(ty::mk_mach_uint(uit))
357 ast::TyFloat(ft) => {
358 if ft == ast::TyF128 && !tcx.sess.features.quad_precision_float.get() {
359 tcx.sess.span_err(path.span, "quadruple precision floats are \
360 missing complete runtime support");
361 tcx.sess.span_note(path.span, "add \
362 #[feature(quad_precision_float)] \
363 to the crate attributes to enable");
365 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
366 Some(ty::mk_mach_float(ft))
369 tcx.sess.span_err(ast_ty.span,
370 "bare `str` is not a type");
371 // return /something/ so they can at least get more errors
372 Some(ty::mk_uniq(tcx, ty::mk_str(tcx)))
383 /// Converts the given AST type to a built-in type. A "built-in type" is, at
384 /// present, either a core numeric type, a string, or `Box`.
385 pub fn ast_ty_to_builtin_ty<AC:AstConv,
391 match ast_ty_to_prim_ty(this.tcx(), ast_ty) {
392 Some(typ) => return Some(typ),
397 ast::TyPath(ref path, _, id) => {
398 let a_def = match this.tcx().def_map.borrow().find(&id) {
402 .span_bug(ast_ty.span,
403 format!("unbound path {}",
404 path_to_str(path)).as_slice())
409 // FIXME(#12938): This is a hack until we have full support for
412 def::DefTy(did) | def::DefStruct(did)
413 if Some(did) == this.tcx().lang_items.owned_box() => {
416 .flat_map(|s| s.types.iter())
421 "`Box` has only one type parameter")
424 for inner_ast_type in path.segments
426 .flat_map(|s| s.types.iter()) {
427 let mt = ast::MutTy {
429 mutbl: ast::MutImmutable,
431 return Some(mk_pointer(this,
436 match ty::get(typ).sty {
441 "`Box<str>` is not a type");
444 ty::ty_vec(_, None) => {
448 "`Box<[T]>` is not a type");
451 _ => ty::mk_uniq(this.tcx(), typ),
455 this.tcx().sess.span_err(path.span,
456 "not enough type parameters \
457 supplied to `Box<T>`");
460 def::DefTy(did) | def::DefStruct(did)
461 if Some(did) == this.tcx().lang_items.gc() => {
464 .flat_map(|s| s.types.iter())
469 "`Gc` has only one type parameter")
472 for inner_ast_type in path.segments
474 .flat_map(|s| s.types.iter()) {
475 let mt = ast::MutTy {
477 mutbl: ast::MutImmutable,
479 return Some(mk_pointer(this,
484 match ty::get(typ).sty {
489 "`Gc<str>` is not a type");
492 ty::ty_vec(_, None) => {
496 "`Gc<[T]>` is not a type");
499 _ => ty::mk_box(this.tcx(), typ),
503 this.tcx().sess.span_bug(path.span,
504 "not enough type parameters \
505 supplied to `Gc<T>`")
520 fn ast_ty_to_mt<AC:AstConv, RS:RegionScope>(this: &AC,
522 ty: &ast::Ty) -> ty::mt {
523 ty::mt {ty: ast_ty_to_ty(this, rscope, ty), mutbl: ast::MutImmutable}
526 pub fn trait_ref_for_unboxed_function<AC:AstConv,
530 unboxed_function: &ast::UnboxedFnTy,
531 self_ty: Option<ty::t>)
534 let fn_mut_trait_did = this.tcx()
536 .require(FnMutTraitLangItem)
539 unboxed_function.decl
543 ast_ty_to_ty(this, rscope, &*input.ty)
544 }).collect::<Vec<_>>();
545 let input_tuple = ty::mk_tup(this.tcx(), input_types);
546 let output_type = ast_ty_to_ty(this,
548 &*unboxed_function.decl.output);
549 let mut substs = Substs::new_type(vec!(input_tuple, output_type),
553 Some(s) => substs.types.push(SelfSpace, s),
558 def_id: fn_mut_trait_did,
563 // Handle `~`, `Box`, and `&` being able to mean strs and vecs.
564 // If a_seq_ty is a str or a vec, make it a str/vec.
565 // Also handle first-class trait types.
566 fn mk_pointer<AC:AstConv,
570 a_seq_ty: &ast::MutTy,
572 constr: |ty::t| -> ty::t)
574 let tcx = this.tcx();
575 debug!("mk_pointer(ptr_ty={:?})", ptr_ty);
577 match a_seq_ty.ty.node {
578 ast::TyVec(ref ty) => {
579 let mut mt = ast_ty_to_mt(this, rscope, &**ty);
580 if a_seq_ty.mutbl == ast::MutMutable {
581 mt.mutbl = ast::MutMutable;
583 return constr(ty::mk_vec(tcx, mt, None));
585 ast::TyUnboxedFn(ref unboxed_function) => {
589 } = trait_ref_for_unboxed_function(this,
593 let tr = ty::mk_trait(this.tcx(),
596 ty::empty_builtin_bounds());
599 return ty::mk_uniq(this.tcx(), tr);
602 return ty::mk_rptr(this.tcx(),
604 ty::mt {mutbl: a_seq_ty.mutbl, ty: tr});
609 "~trait or &trait are the only supported \
610 forms of casting-to-trait");
616 ast::TyPath(ref path, ref bounds, id) => {
617 // Note that the "bounds must be empty if path is not a trait"
618 // restriction is enforced in the below case for ty_path, which
619 // will run after this as long as the path isn't a trait.
620 match tcx.def_map.borrow().find(&id) {
621 Some(&def::DefPrimTy(ast::TyStr)) => {
622 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
625 return constr(ty::mk_str(tcx));
628 return ty::mk_str_slice(tcx, r, ast::MutImmutable);
633 "managed strings are not supported")
637 Some(&def::DefTrait(trait_def_id)) => {
638 let result = ast_path_to_trait_ref(
639 this, rscope, trait_def_id, None, path);
640 let trait_store = match ptr_ty {
641 Uniq => ty::UniqTraitStore,
643 ty::RegionTraitStore(r, a_seq_ty.mutbl)
648 "~trait or &trait are the only supported \
649 forms of casting-to-trait");
653 let bounds = conv_builtin_bounds(this.tcx(),
657 let tr = ty::mk_trait(tcx,
659 result.substs.clone(),
661 // We could just match on ptr_ty, but we need to pass a trait
662 // store to conv_builtin_bounds, so mathc twice for now.
663 return match trait_store {
664 ty::UniqTraitStore => {
665 return ty::mk_uniq(tcx, tr);
667 ty::RegionTraitStore(r, m) => {
668 return ty::mk_rptr(tcx, r, ty::mt{mutbl: m, ty: tr});
678 constr(ast_ty_to_ty(this, rscope, &*a_seq_ty.ty))
681 // Parses the programmer's textual representation of a type into our
682 // internal notion of a type.
683 pub fn ast_ty_to_ty<AC:AstConv, RS:RegionScope>(
684 this: &AC, rscope: &RS, ast_ty: &ast::Ty) -> ty::t {
686 let tcx = this.tcx();
688 let mut ast_ty_to_ty_cache = tcx.ast_ty_to_ty_cache.borrow_mut();
689 match ast_ty_to_ty_cache.find(&ast_ty.id) {
690 Some(&ty::atttce_resolved(ty)) => return ty,
691 Some(&ty::atttce_unresolved) => {
692 tcx.sess.span_fatal(ast_ty.span,
693 "illegal recursive type; insert an enum \
694 or struct in the cycle, if this is \
697 None => { /* go on */ }
699 ast_ty_to_ty_cache.insert(ast_ty.id, ty::atttce_unresolved);
700 drop(ast_ty_to_ty_cache);
702 let typ = ast_ty_to_builtin_ty(this, rscope, ast_ty).unwrap_or_else(|| {
704 ast::TyNil => ty::mk_nil(),
705 ast::TyBot => ty::mk_bot(),
707 let mt = ast::MutTy { ty: ty, mutbl: ast::MutImmutable };
708 mk_pointer(this, rscope, &mt, Box, |ty| ty::mk_box(tcx, ty))
711 let mt = ast::MutTy { ty: ty, mutbl: ast::MutImmutable };
712 mk_pointer(this, rscope, &mt, Uniq,
713 |ty| ty::mk_uniq(tcx, ty))
716 tcx.sess.span_err(ast_ty.span, "bare `[]` is not a type");
717 // return /something/ so they can at least get more errors
718 let vec_ty = ty::mk_vec(tcx, ast_ty_to_mt(this, rscope, &*ty), None);
719 ty::mk_uniq(tcx, vec_ty)
721 ast::TyPtr(ref mt) => {
722 ty::mk_ptr(tcx, ty::mt {
723 ty: ast_ty_to_ty(this, rscope, &*mt.ty),
727 ast::TyRptr(ref region, ref mt) => {
728 let r = opt_ast_region_to_region(this, rscope, ast_ty.span, region);
729 debug!("ty_rptr r={}", r.repr(this.tcx()));
730 mk_pointer(this, rscope, mt, RPtr(r),
731 |ty| ty::mk_rptr(tcx, r, ty::mt {ty: ty, mutbl: mt.mutbl}))
733 ast::TyTup(ref fields) => {
734 let flds = fields.iter()
735 .map(|t| ast_ty_to_ty(this, rscope, &**t))
737 ty::mk_tup(tcx, flds)
739 ast::TyParen(ref typ) => ast_ty_to_ty(this, rscope, &**typ),
740 ast::TyBareFn(ref bf) => {
741 if bf.decl.variadic && bf.abi != abi::C {
742 tcx.sess.span_err(ast_ty.span,
743 "variadic function must have C calling convention");
745 ty::mk_bare_fn(tcx, ty_of_bare_fn(this, ast_ty.id, bf.fn_style,
748 ast::TyClosure(ref f, ref region) => {
750 // resolve the function bound region in the original region
751 // scope `rscope`, not the scope of the function parameters
752 let bound_region = opt_ast_region_to_region(this, rscope,
753 ast_ty.span, region);
755 let store = ty::RegionTraitStore(bound_region, ast::MutMutable);
757 // Use corresponding trait store to figure out default bounds
758 // if none were specified.
759 let bounds = conv_builtin_bounds(this.tcx(),
764 let fn_decl = ty_of_closure(this,
772 ty::mk_closure(tcx, fn_decl)
774 ast::TyProc(ref f) => {
775 // Use corresponding trait store to figure out default bounds
776 // if none were specified.
777 let bounds = conv_builtin_bounds(this.tcx(),
782 let fn_decl = ty_of_closure(this,
790 ty::mk_closure(tcx, fn_decl)
792 ast::TyUnboxedFn(_) => {
793 tcx.sess.span_err(ast_ty.span,
794 "cannot use unboxed functions here");
797 ast::TyPath(ref path, ref bounds, id) => {
798 let a_def = match tcx.def_map.borrow().find(&id) {
801 .span_bug(ast_ty.span,
802 format!("unbound path {}",
803 path_to_str(path)).as_slice())
807 // Kind bounds on path types are only supported for traits.
809 // But don't emit the error if the user meant to do a trait anyway.
810 def::DefTrait(..) => { },
811 _ if bounds.is_some() =>
812 tcx.sess.span_err(ast_ty.span,
813 "kind bounds can only be used on trait types"),
817 def::DefTrait(_) => {
818 let path_str = path_to_str(path);
821 format!("reference to trait `{name}` where a \
822 type is expected; try `Box<{name}>` or \
824 name=path_str).as_slice());
827 def::DefTy(did) | def::DefStruct(did) => {
828 ast_path_to_ty(this, rscope, did, path).ty
830 def::DefTyParam(space, id, n) => {
831 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
832 ty::mk_param(tcx, space, n, id)
834 def::DefSelfTy(id) => {
835 // n.b.: resolve guarantees that the this type only appears in a
836 // trait, which we rely upon in various places when creating
838 check_path_args(tcx, path, NO_TPS | NO_REGIONS);
839 let did = ast_util::local_def(id);
840 ty::mk_self_type(tcx, did)
843 tcx.sess.span_fatal(ast_ty.span,
844 format!("found module name used as a type: {}",
845 tcx.map.node_to_str(id.node)).as_slice());
847 def::DefPrimTy(_) => {
848 fail!("DefPrimTy arm missed in previous ast_ty_to_prim_ty call");
851 tcx.sess.span_fatal(ast_ty.span,
852 format!("found value name used \
858 ast::TyFixedLengthVec(ty, e) => {
859 match const_eval::eval_const_expr_partial(tcx, &*e) {
862 const_eval::const_int(i) =>
863 ty::mk_vec(tcx, ast_ty_to_mt(this, rscope, &*ty),
865 const_eval::const_uint(i) =>
866 ty::mk_vec(tcx, ast_ty_to_mt(this, rscope, &*ty),
870 ast_ty.span, "expected constant expr for vector length");
877 format!("expected constant expr for vector \
883 ast::TyTypeof(_e) => {
884 tcx.sess.span_bug(ast_ty.span, "typeof is reserved but unimplemented");
887 // TyInfer also appears as the type of arguments or return
888 // values in a ExprFnBlock or ExprProc, or as the type of
889 // local variables. Both of these cases are handled specially
890 // and will not descend into this routine.
891 this.ty_infer(ast_ty.span)
896 tcx.ast_ty_to_ty_cache.borrow_mut().insert(ast_ty.id, ty::atttce_resolved(typ));
900 pub fn ty_of_arg<AC: AstConv, RS: RegionScope>(this: &AC, rscope: &RS, a: &ast::Arg,
901 expected_ty: Option<ty::t>) -> ty::t {
903 ast::TyInfer if expected_ty.is_some() => expected_ty.unwrap(),
904 ast::TyInfer => this.ty_infer(a.ty.span),
905 _ => ast_ty_to_ty(this, rscope, &*a.ty),
910 untransformed_self_ty: ty::t,
911 explicit_self: ast::ExplicitSelf
914 pub fn ty_of_method<AC:AstConv>(
917 fn_style: ast::FnStyle,
918 untransformed_self_ty: ty::t,
919 explicit_self: ast::ExplicitSelf,
923 ty_of_method_or_bare_fn(this, id, fn_style, abi::Rust, Some(SelfInfo {
924 untransformed_self_ty: untransformed_self_ty,
925 explicit_self: explicit_self
929 pub fn ty_of_bare_fn<AC:AstConv>(this: &AC, id: ast::NodeId,
930 fn_style: ast::FnStyle, abi: abi::Abi,
931 decl: &ast::FnDecl) -> ty::BareFnTy {
932 ty_of_method_or_bare_fn(this, id, fn_style, abi, None, decl)
935 fn ty_of_method_or_bare_fn<AC:AstConv>(this: &AC, id: ast::NodeId,
936 fn_style: ast::FnStyle, abi: abi::Abi,
937 opt_self_info: Option<SelfInfo>,
938 decl: &ast::FnDecl) -> ty::BareFnTy {
939 debug!("ty_of_method_or_bare_fn");
941 // new region names that appear inside of the fn decl are bound to
942 // that function type
943 let rb = rscope::BindingRscope::new(id);
945 let self_ty = opt_self_info.and_then(|self_info| {
946 match self_info.explicit_self.node {
947 ast::SelfStatic => None,
949 Some(self_info.untransformed_self_ty)
951 ast::SelfRegion(ref lifetime, mutability) => {
953 opt_ast_region_to_region(this, &rb,
954 self_info.explicit_self.span,
956 Some(ty::mk_rptr(this.tcx(), region,
957 ty::mt {ty: self_info.untransformed_self_ty,
961 Some(ty::mk_uniq(this.tcx(), self_info.untransformed_self_ty))
966 // HACK(eddyb) replace the fake self type in the AST with the actual type.
967 let input_tys = if self_ty.is_some() {
968 decl.inputs.slice_from(1)
970 decl.inputs.as_slice()
972 let input_tys = input_tys.iter().map(|a| ty_of_arg(this, &rb, a, None));
974 let self_and_input_tys = self_ty.move_iter().chain(input_tys).collect();
976 let output_ty = match decl.output.node {
977 ast::TyInfer => this.ty_infer(decl.output.span),
978 _ => ast_ty_to_ty(this, &rb, &*decl.output)
981 return ty::BareFnTy {
986 inputs: self_and_input_tys,
988 variadic: decl.variadic
993 pub fn ty_of_closure<AC:AstConv>(
996 fn_style: ast::FnStyle,
997 onceness: ast::Onceness,
998 bounds: ty::BuiltinBounds,
999 store: ty::TraitStore,
1001 expected_sig: Option<ty::FnSig>)
1004 debug!("ty_of_fn_decl");
1006 // new region names that appear inside of the fn decl are bound to
1007 // that function type
1008 let rb = rscope::BindingRscope::new(id);
1010 let input_tys = decl.inputs.iter().enumerate().map(|(i, a)| {
1011 let expected_arg_ty = expected_sig.as_ref().and_then(|e| {
1012 // no guarantee that the correct number of expected args
1014 if i < e.inputs.len() {
1015 Some(*e.inputs.get(i))
1020 ty_of_arg(this, &rb, a, expected_arg_ty)
1023 let expected_ret_ty = expected_sig.map(|e| e.output);
1024 let output_ty = match decl.output.node {
1025 ast::TyInfer if expected_ret_ty.is_some() => expected_ret_ty.unwrap(),
1026 ast::TyInfer => this.ty_infer(decl.output.span),
1027 _ => ast_ty_to_ty(this, &rb, &*decl.output)
1035 sig: ty::FnSig {binder_id: id,
1038 variadic: decl.variadic}
1042 fn conv_builtin_bounds(tcx: &ty::ctxt,
1044 ast_bounds: &Option<OwnedSlice<ast::TyParamBound>>,
1045 store: ty::TraitStore)
1046 -> ty::BuiltinBounds {
1047 //! Converts a list of bounds from the AST into a `BuiltinBounds`
1048 //! struct. Reports an error if any of the bounds that appear
1049 //! in the AST refer to general traits and not the built-in traits
1050 //! like `Send`. Used to translate the bounds that
1051 //! appear in closure and trait types, where only builtin bounds are
1053 //! If no bounds were specified, we choose a "default" bound based on
1054 //! the allocation type of the fn/trait, as per issue #7264. The user can
1055 //! override this with an empty bounds list, e.g. "Box<fn:()>" or
1058 match (ast_bounds, store) {
1059 (&Some(ref bound_vec), _) => {
1060 let mut builtin_bounds = ty::empty_builtin_bounds();
1061 for ast_bound in bound_vec.iter() {
1063 ast::TraitTyParamBound(ref b) => {
1064 match lookup_def_tcx(tcx, b.path.span, b.ref_id) {
1065 def::DefTrait(trait_did) => {
1066 if ty::try_add_builtin_trait(tcx, trait_did,
1067 &mut builtin_bounds) {
1068 continue; // success
1073 tcx.sess.span_fatal(
1075 "only the builtin traits can be used as closure \
1078 ast::StaticRegionTyParamBound => {
1079 builtin_bounds.add(ty::BoundStatic);
1081 ast::UnboxedFnTyParamBound(_) => {
1082 tcx.sess.span_err(span,
1083 "unboxed functions are not allowed \
1086 ast::OtherRegionTyParamBound(span) => {
1087 if !tcx.sess.features.issue_5723_bootstrap.get() {
1090 "only the 'static lifetime is accepted \
1098 // &'static Trait is sugar for &'static Trait:'static.
1099 (&None, ty::RegionTraitStore(ty::ReStatic, _)) => {
1100 let mut set = ty::empty_builtin_bounds(); set.add(ty::BoundStatic); set
1102 // No bounds are automatically applied for &'r Trait or ~Trait
1103 (&None, ty::RegionTraitStore(..)) |
1104 (&None, ty::UniqTraitStore) => ty::empty_builtin_bounds(),