1 // Copyright 2015 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.
11 // Lowers the AST to the HIR
15 use std::collections::HashMap;
19 use syntax::codemap::{respan, Spanned, Span};
20 use syntax::owned_slice::OwnedSlice;
21 use syntax::parse::token::{self, str_to_ident};
22 use syntax::std_inject;
24 use std::cell::{Cell, RefCell};
26 pub struct LoweringContext<'a> {
27 crate_root: Option<&'static str>,
28 id_cache: RefCell<HashMap<NodeId, NodeId>>,
29 id_assigner: &'a NodeIdAssigner,
33 impl<'a, 'hir> LoweringContext<'a> {
34 pub fn new(id_assigner: &'a NodeIdAssigner, c: &Crate) -> LoweringContext<'a> {
35 let crate_root = if std_inject::no_core(c) {
37 } else if std_inject::no_std(c) {
44 crate_root: crate_root,
45 id_cache: RefCell::new(HashMap::new()),
46 id_assigner: id_assigner,
47 cached_id: Cell::new(0),
51 fn next_id(&self) -> NodeId {
52 let cached = self.cached_id.get();
54 return self.id_assigner.next_node_id()
57 self.cached_id.set(cached + 1);
62 pub fn lower_view_path(_lctx: &LoweringContext, view_path: &ViewPath) -> P<hir::ViewPath> {
64 node: match view_path.node {
65 ViewPathSimple(ident, ref path) => {
66 hir::ViewPathSimple(ident.name, lower_path(_lctx, path))
68 ViewPathGlob(ref path) => {
69 hir::ViewPathGlob(lower_path(_lctx, path))
71 ViewPathList(ref path, ref path_list_idents) => {
72 hir::ViewPathList(lower_path(_lctx, path),
73 path_list_idents.iter().map(|path_list_ident| {
75 node: match path_list_ident.node {
76 PathListIdent { id, name, rename } =>
80 rename: rename.map(|x| x.name),
82 PathListMod { id, rename } =>
85 rename: rename.map(|x| x.name)
88 span: path_list_ident.span
97 pub fn lower_arm(_lctx: &LoweringContext, arm: &Arm) -> hir::Arm {
99 attrs: arm.attrs.clone(),
100 pats: arm.pats.iter().map(|x| lower_pat(_lctx, x)).collect(),
101 guard: arm.guard.as_ref().map(|ref x| lower_expr(_lctx, x)),
102 body: lower_expr(_lctx, &arm.body),
106 pub fn lower_decl(_lctx: &LoweringContext, d: &Decl) -> P<hir::Decl> {
108 DeclLocal(ref l) => P(Spanned {
109 node: hir::DeclLocal(lower_local(_lctx, l)),
112 DeclItem(ref it) => P(Spanned {
113 node: hir::DeclItem(lower_item(_lctx, it)),
119 pub fn lower_ty_binding(_lctx: &LoweringContext, b: &TypeBinding) -> P<hir::TypeBinding> {
120 P(hir::TypeBinding { id: b.id, name: b.ident.name, ty: lower_ty(_lctx, &b.ty), span: b.span })
123 pub fn lower_ty(_lctx: &LoweringContext, t: &Ty) -> P<hir::Ty> {
127 TyInfer => hir::TyInfer,
128 TyVec(ref ty) => hir::TyVec(lower_ty(_lctx, ty)),
129 TyPtr(ref mt) => hir::TyPtr(lower_mt(_lctx, mt)),
130 TyRptr(ref region, ref mt) => {
131 hir::TyRptr(lower_opt_lifetime(_lctx, region), lower_mt(_lctx, mt))
134 hir::TyBareFn(P(hir::BareFnTy {
135 lifetimes: lower_lifetime_defs(_lctx, &f.lifetimes),
136 unsafety: lower_unsafety(_lctx, f.unsafety),
138 decl: lower_fn_decl(_lctx, &f.decl),
141 TyTup(ref tys) => hir::TyTup(tys.iter().map(|ty| lower_ty(_lctx, ty)).collect()),
142 TyParen(ref ty) => hir::TyParen(lower_ty(_lctx, ty)),
143 TyPath(ref qself, ref path) => {
144 let qself = qself.as_ref().map(|&QSelf { ref ty, position }| {
146 ty: lower_ty(_lctx, ty),
150 hir::TyPath(qself, lower_path(_lctx, path))
152 TyObjectSum(ref ty, ref bounds) => {
153 hir::TyObjectSum(lower_ty(_lctx, ty),
154 lower_bounds(_lctx, bounds))
156 TyFixedLengthVec(ref ty, ref e) => {
157 hir::TyFixedLengthVec(lower_ty(_lctx, ty), lower_expr(_lctx, e))
159 TyTypeof(ref expr) => {
160 hir::TyTypeof(lower_expr(_lctx, expr))
162 TyPolyTraitRef(ref bounds) => {
163 hir::TyPolyTraitRef(bounds.iter().map(|b| lower_ty_param_bound(_lctx, b)).collect())
165 TyMac(_) => panic!("TyMac should have been expanded by now."),
171 pub fn lower_foreign_mod(_lctx: &LoweringContext, fm: &ForeignMod) -> hir::ForeignMod {
174 items: fm.items.iter().map(|x| lower_foreign_item(_lctx, x)).collect(),
178 pub fn lower_variant(_lctx: &LoweringContext, v: &Variant) -> P<hir::Variant> {
180 node: hir::Variant_ {
182 name: v.node.name.name,
183 attrs: v.node.attrs.clone(),
184 kind: match v.node.kind {
185 TupleVariantKind(ref variant_args) => {
186 hir::TupleVariantKind(variant_args.iter().map(|ref x|
187 lower_variant_arg(_lctx, x)).collect())
189 StructVariantKind(ref struct_def) => {
190 hir::StructVariantKind(lower_struct_def(_lctx, struct_def))
193 disr_expr: v.node.disr_expr.as_ref().map(|e| lower_expr(_lctx, e)),
199 pub fn lower_path(_lctx: &LoweringContext, p: &Path) -> hir::Path {
202 segments: p.segments.iter().map(|&PathSegment {identifier, ref parameters}|
204 identifier: identifier,
205 parameters: lower_path_parameters(_lctx, parameters),
211 pub fn lower_path_parameters(_lctx: &LoweringContext,
212 path_parameters: &PathParameters)
213 -> hir::PathParameters {
214 match *path_parameters {
215 AngleBracketedParameters(ref data) =>
216 hir::AngleBracketedParameters(lower_angle_bracketed_parameter_data(_lctx, data)),
217 ParenthesizedParameters(ref data) =>
218 hir::ParenthesizedParameters(lower_parenthesized_parameter_data(_lctx, data)),
222 pub fn lower_angle_bracketed_parameter_data(_lctx: &LoweringContext,
223 data: &AngleBracketedParameterData)
224 -> hir::AngleBracketedParameterData {
225 let &AngleBracketedParameterData { ref lifetimes, ref types, ref bindings } = data;
226 hir::AngleBracketedParameterData {
227 lifetimes: lower_lifetimes(_lctx, lifetimes),
228 types: types.iter().map(|ty| lower_ty(_lctx, ty)).collect(),
229 bindings: bindings.iter().map(|b| lower_ty_binding(_lctx, b)).collect(),
233 pub fn lower_parenthesized_parameter_data(_lctx: &LoweringContext,
234 data: &ParenthesizedParameterData)
235 -> hir::ParenthesizedParameterData {
236 let &ParenthesizedParameterData { ref inputs, ref output, span } = data;
237 hir::ParenthesizedParameterData {
238 inputs: inputs.iter().map(|ty| lower_ty(_lctx, ty)).collect(),
239 output: output.as_ref().map(|ty| lower_ty(_lctx, ty)),
244 pub fn lower_local(_lctx: &LoweringContext, l: &Local) -> P<hir::Local> {
247 ty: l.ty.as_ref().map(|t| lower_ty(_lctx, t)),
248 pat: lower_pat(_lctx, &l.pat),
249 init: l.init.as_ref().map(|e| lower_expr(_lctx, e)),
254 pub fn lower_explicit_self_underscore(_lctx: &LoweringContext,
256 -> hir::ExplicitSelf_ {
258 SelfStatic => hir::SelfStatic,
259 SelfValue(v) => hir::SelfValue(v.name),
260 SelfRegion(ref lifetime, m, ident) => {
261 hir::SelfRegion(lower_opt_lifetime(_lctx, lifetime),
262 lower_mutability(_lctx, m),
265 SelfExplicit(ref typ, ident) => {
266 hir::SelfExplicit(lower_ty(_lctx, typ), ident.name)
271 pub fn lower_mutability(_lctx: &LoweringContext, m: Mutability) -> hir::Mutability {
273 MutMutable => hir::MutMutable,
274 MutImmutable => hir::MutImmutable,
278 pub fn lower_explicit_self(_lctx: &LoweringContext, s: &ExplicitSelf) -> hir::ExplicitSelf {
279 Spanned { node: lower_explicit_self_underscore(_lctx, &s.node), span: s.span }
282 pub fn lower_arg(_lctx: &LoweringContext, arg: &Arg) -> hir::Arg {
283 hir::Arg { id: arg.id, pat: lower_pat(_lctx, &arg.pat), ty: lower_ty(_lctx, &arg.ty) }
286 pub fn lower_fn_decl(_lctx: &LoweringContext, decl: &FnDecl) -> P<hir::FnDecl> {
288 inputs: decl.inputs.iter().map(|x| lower_arg(_lctx, x)).collect(),
289 output: match decl.output {
290 Return(ref ty) => hir::Return(lower_ty(_lctx, ty)),
291 DefaultReturn(span) => hir::DefaultReturn(span),
292 NoReturn(span) => hir::NoReturn(span),
294 variadic: decl.variadic,
298 pub fn lower_ty_param_bound(_lctx: &LoweringContext, tpb: &TyParamBound) -> hir::TyParamBound {
300 TraitTyParamBound(ref ty, modifier) => {
301 hir::TraitTyParamBound(lower_poly_trait_ref(_lctx, ty),
302 lower_trait_bound_modifier(_lctx, modifier))
304 RegionTyParamBound(ref lifetime) => {
305 hir::RegionTyParamBound(lower_lifetime(_lctx, lifetime))
310 pub fn lower_ty_param(_lctx: &LoweringContext, tp: &TyParam) -> hir::TyParam {
314 bounds: lower_bounds(_lctx, &tp.bounds),
315 default: tp.default.as_ref().map(|x| lower_ty(_lctx, x)),
320 pub fn lower_ty_params(_lctx: &LoweringContext,
321 tps: &OwnedSlice<TyParam>)
322 -> OwnedSlice<hir::TyParam> {
323 tps.iter().map(|tp| lower_ty_param(_lctx, tp)).collect()
326 pub fn lower_lifetime(_lctx: &LoweringContext, l: &Lifetime) -> hir::Lifetime {
327 hir::Lifetime { id: l.id, name: l.name, span: l.span }
330 pub fn lower_lifetime_def(_lctx: &LoweringContext, l: &LifetimeDef) -> hir::LifetimeDef {
332 lifetime: lower_lifetime(_lctx, &l.lifetime),
333 bounds: lower_lifetimes(_lctx, &l.bounds)
337 pub fn lower_lifetimes(_lctx: &LoweringContext, lts: &Vec<Lifetime>) -> Vec<hir::Lifetime> {
338 lts.iter().map(|l| lower_lifetime(_lctx, l)).collect()
341 pub fn lower_lifetime_defs(_lctx: &LoweringContext,
342 lts: &Vec<LifetimeDef>)
343 -> Vec<hir::LifetimeDef> {
344 lts.iter().map(|l| lower_lifetime_def(_lctx, l)).collect()
347 pub fn lower_opt_lifetime(_lctx: &LoweringContext,
348 o_lt: &Option<Lifetime>)
349 -> Option<hir::Lifetime> {
350 o_lt.as_ref().map(|lt| lower_lifetime(_lctx, lt))
353 pub fn lower_generics(_lctx: &LoweringContext, g: &Generics) -> hir::Generics {
355 ty_params: lower_ty_params(_lctx, &g.ty_params),
356 lifetimes: lower_lifetime_defs(_lctx, &g.lifetimes),
357 where_clause: lower_where_clause(_lctx, &g.where_clause),
361 pub fn lower_where_clause(_lctx: &LoweringContext, wc: &WhereClause) -> hir::WhereClause {
364 predicates: wc.predicates.iter().map(|predicate|
365 lower_where_predicate(_lctx, predicate)).collect(),
369 pub fn lower_where_predicate(_lctx: &LoweringContext,
370 pred: &WherePredicate)
371 -> hir::WherePredicate {
373 WherePredicate::BoundPredicate(WhereBoundPredicate{ ref bound_lifetimes,
377 hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate {
378 bound_lifetimes: lower_lifetime_defs(_lctx, bound_lifetimes),
379 bounded_ty: lower_ty(_lctx, bounded_ty),
380 bounds: bounds.iter().map(|x| lower_ty_param_bound(_lctx, x)).collect(),
384 WherePredicate::RegionPredicate(WhereRegionPredicate{ ref lifetime,
387 hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate {
389 lifetime: lower_lifetime(_lctx, lifetime),
390 bounds: bounds.iter().map(|bound| lower_lifetime(_lctx, bound)).collect()
393 WherePredicate::EqPredicate(WhereEqPredicate{ id,
397 hir::WherePredicate::EqPredicate(hir::WhereEqPredicate {
399 path: lower_path(_lctx, path),
400 ty:lower_ty(_lctx, ty),
407 pub fn lower_struct_def(_lctx: &LoweringContext, sd: &StructDef) -> P<hir::StructDef> {
409 fields: sd.fields.iter().map(|f| lower_struct_field(_lctx, f)).collect(),
414 pub fn lower_trait_ref(_lctx: &LoweringContext, p: &TraitRef) -> hir::TraitRef {
415 hir::TraitRef { path: lower_path(_lctx, &p.path), ref_id: p.ref_id }
418 pub fn lower_poly_trait_ref(_lctx: &LoweringContext, p: &PolyTraitRef) -> hir::PolyTraitRef {
420 bound_lifetimes: lower_lifetime_defs(_lctx, &p.bound_lifetimes),
421 trait_ref: lower_trait_ref(_lctx, &p.trait_ref),
426 pub fn lower_struct_field(_lctx: &LoweringContext, f: &StructField) -> hir::StructField {
428 node: hir::StructField_ {
430 kind: lower_struct_field_kind(_lctx, &f.node.kind),
431 ty: lower_ty(_lctx, &f.node.ty),
432 attrs: f.node.attrs.clone(),
438 pub fn lower_field(_lctx: &LoweringContext, f: &Field) -> hir::Field {
440 name: respan(f.ident.span, f.ident.node.name),
441 expr: lower_expr(_lctx, &f.expr), span: f.span
445 pub fn lower_mt(_lctx: &LoweringContext, mt: &MutTy) -> hir::MutTy {
446 hir::MutTy { ty: lower_ty(_lctx, &mt.ty), mutbl: lower_mutability(_lctx, mt.mutbl) }
449 pub fn lower_opt_bounds(_lctx: &LoweringContext, b: &Option<OwnedSlice<TyParamBound>>)
450 -> Option<OwnedSlice<hir::TyParamBound>> {
451 b.as_ref().map(|ref bounds| lower_bounds(_lctx, bounds))
454 fn lower_bounds(_lctx: &LoweringContext, bounds: &TyParamBounds) -> hir::TyParamBounds {
455 bounds.iter().map(|bound| lower_ty_param_bound(_lctx, bound)).collect()
458 fn lower_variant_arg(_lctx: &LoweringContext, va: &VariantArg) -> hir::VariantArg {
459 hir::VariantArg { id: va.id, ty: lower_ty(_lctx, &va.ty) }
462 pub fn lower_block(_lctx: &LoweringContext, b: &Block) -> P<hir::Block> {
465 stmts: b.stmts.iter().map(|s| lower_stmt(_lctx, s)).collect(),
466 expr: b.expr.as_ref().map(|ref x| lower_expr(_lctx, x)),
467 rules: lower_block_check_mode(_lctx, &b.rules),
472 pub fn lower_item_underscore(_lctx: &LoweringContext, i: &Item_) -> hir::Item_ {
474 ItemExternCrate(string) => hir::ItemExternCrate(string),
475 ItemUse(ref view_path) => {
476 hir::ItemUse(lower_view_path(_lctx, view_path))
478 ItemStatic(ref t, m, ref e) => {
479 hir::ItemStatic(lower_ty(_lctx, t), lower_mutability(_lctx, m), lower_expr(_lctx, e))
481 ItemConst(ref t, ref e) => {
482 hir::ItemConst(lower_ty(_lctx, t), lower_expr(_lctx, e))
484 ItemFn(ref decl, unsafety, constness, abi, ref generics, ref body) => {
486 lower_fn_decl(_lctx, decl),
487 lower_unsafety(_lctx, unsafety),
488 lower_constness(_lctx, constness),
490 lower_generics(_lctx, generics),
491 lower_block(_lctx, body)
494 ItemMod(ref m) => hir::ItemMod(lower_mod(_lctx, m)),
495 ItemForeignMod(ref nm) => hir::ItemForeignMod(lower_foreign_mod(_lctx, nm)),
496 ItemTy(ref t, ref generics) => {
497 hir::ItemTy(lower_ty(_lctx, t), lower_generics(_lctx, generics))
499 ItemEnum(ref enum_definition, ref generics) => {
502 variants: enum_definition.variants.iter().map(|x| {
503 lower_variant(_lctx, x)
506 lower_generics(_lctx, generics))
508 ItemStruct(ref struct_def, ref generics) => {
509 let struct_def = lower_struct_def(_lctx, struct_def);
510 hir::ItemStruct(struct_def, lower_generics(_lctx, generics))
512 ItemDefaultImpl(unsafety, ref trait_ref) => {
513 hir::ItemDefaultImpl(lower_unsafety(_lctx, unsafety), lower_trait_ref(_lctx, trait_ref))
515 ItemImpl(unsafety, polarity, ref generics, ref ifce, ref ty, ref impl_items) => {
517 impl_items.iter().map(|item| lower_impl_item(_lctx, item)).collect();
518 let ifce = ifce.as_ref().map(|trait_ref| lower_trait_ref(_lctx, trait_ref));
519 hir::ItemImpl(lower_unsafety(_lctx, unsafety),
520 lower_impl_polarity(_lctx, polarity),
521 lower_generics(_lctx, generics),
526 ItemTrait(unsafety, ref generics, ref bounds, ref items) => {
527 let bounds = lower_bounds(_lctx, bounds);
528 let items = items.iter().map(|item| lower_trait_item(_lctx, item)).collect();
529 hir::ItemTrait(lower_unsafety(_lctx, unsafety),
530 lower_generics(_lctx, generics),
534 ItemMac(_) => panic!("Shouldn't still be around"),
538 pub fn lower_trait_item(_lctx: &LoweringContext, i: &TraitItem) -> P<hir::TraitItem> {
542 attrs: i.attrs.clone(),
544 ConstTraitItem(ref ty, ref default) => {
545 hir::ConstTraitItem(lower_ty(_lctx, ty),
546 default.as_ref().map(|x| lower_expr(_lctx, x)))
548 MethodTraitItem(ref sig, ref body) => {
549 hir::MethodTraitItem(lower_method_sig(_lctx, sig),
550 body.as_ref().map(|x| lower_block(_lctx, x)))
552 TypeTraitItem(ref bounds, ref default) => {
553 hir::TypeTraitItem(lower_bounds(_lctx, bounds),
554 default.as_ref().map(|x| lower_ty(_lctx, x)))
561 pub fn lower_impl_item(_lctx: &LoweringContext, i: &ImplItem) -> P<hir::ImplItem> {
565 attrs: i.attrs.clone(),
566 vis: lower_visibility(_lctx, i.vis),
568 ConstImplItem(ref ty, ref expr) => {
569 hir::ConstImplItem(lower_ty(_lctx, ty), lower_expr(_lctx, expr))
571 MethodImplItem(ref sig, ref body) => {
572 hir::MethodImplItem(lower_method_sig(_lctx, sig),
573 lower_block(_lctx, body))
575 TypeImplItem(ref ty) => hir::TypeImplItem(lower_ty(_lctx, ty)),
576 MacImplItem(..) => panic!("Shouldn't exist any more"),
582 pub fn lower_mod(_lctx: &LoweringContext, m: &Mod) -> hir::Mod {
583 hir::Mod { inner: m.inner, items: m.items.iter().map(|x| lower_item(_lctx, x)).collect() }
586 pub fn lower_crate(_lctx: &LoweringContext, c: &Crate) -> hir::Crate {
588 module: lower_mod(_lctx, &c.module),
589 attrs: c.attrs.clone(),
590 config: c.config.clone(),
592 exported_macros: c.exported_macros.iter().map(|m| lower_macro_def(_lctx, m)).collect(),
596 pub fn lower_macro_def(_lctx: &LoweringContext, m: &MacroDef) -> hir::MacroDef {
599 attrs: m.attrs.clone(),
602 imported_from: m.imported_from.map(|x| x.name),
604 use_locally: m.use_locally,
605 allow_internal_unstable: m.allow_internal_unstable,
606 body: m.body.clone(),
610 // fold one item into possibly many items
611 pub fn lower_item(_lctx: &LoweringContext, i: &Item) -> P<hir::Item> {
612 P(lower_item_simple(_lctx, i))
615 // fold one item into exactly one item
616 pub fn lower_item_simple(_lctx: &LoweringContext, i: &Item) -> hir::Item {
617 let node = lower_item_underscore(_lctx, &i.node);
622 attrs: i.attrs.clone(),
624 vis: lower_visibility(_lctx, i.vis),
629 pub fn lower_foreign_item(_lctx: &LoweringContext, i: &ForeignItem) -> P<hir::ForeignItem> {
633 attrs: i.attrs.clone(),
635 ForeignItemFn(ref fdec, ref generics) => {
636 hir::ForeignItemFn(lower_fn_decl(_lctx, fdec), lower_generics(_lctx, generics))
638 ForeignItemStatic(ref t, m) => {
639 hir::ForeignItemStatic(lower_ty(_lctx, t), m)
642 vis: lower_visibility(_lctx, i.vis),
647 pub fn lower_method_sig(_lctx: &LoweringContext, sig: &MethodSig) -> hir::MethodSig {
649 generics: lower_generics(_lctx, &sig.generics),
651 explicit_self: lower_explicit_self(_lctx, &sig.explicit_self),
652 unsafety: lower_unsafety(_lctx, sig.unsafety),
653 constness: lower_constness(_lctx, sig.constness),
654 decl: lower_fn_decl(_lctx, &sig.decl),
658 pub fn lower_unsafety(_lctx: &LoweringContext, u: Unsafety) -> hir::Unsafety {
660 Unsafety::Unsafe => hir::Unsafety::Unsafe,
661 Unsafety::Normal => hir::Unsafety::Normal,
665 pub fn lower_constness(_lctx: &LoweringContext, c: Constness) -> hir::Constness {
667 Constness::Const => hir::Constness::Const,
668 Constness::NotConst => hir::Constness::NotConst,
672 pub fn lower_unop(_lctx: &LoweringContext, u: UnOp) -> hir::UnOp {
674 UnDeref => hir::UnDeref,
680 pub fn lower_binop(_lctx: &LoweringContext, b: BinOp) -> hir::BinOp {
690 BiBitXor => hir::BiBitXor,
691 BiBitAnd => hir::BiBitAnd,
692 BiBitOr => hir::BiBitOr,
706 pub fn lower_pat(_lctx: &LoweringContext, p: &Pat) -> P<hir::Pat> {
710 PatWild(k) => hir::PatWild(lower_pat_wild_kind(_lctx, k)),
711 PatIdent(ref binding_mode, pth1, ref sub) => {
712 hir::PatIdent(lower_binding_mode(_lctx, binding_mode),
714 sub.as_ref().map(|x| lower_pat(_lctx, x)))
716 PatLit(ref e) => hir::PatLit(lower_expr(_lctx, e)),
717 PatEnum(ref pth, ref pats) => {
718 hir::PatEnum(lower_path(_lctx, pth),
720 .map(|pats| pats.iter().map(|x| lower_pat(_lctx, x)).collect()))
722 PatQPath(ref qself, ref pth) => {
723 let qself = hir::QSelf {
724 ty: lower_ty(_lctx, &qself.ty),
725 position: qself.position,
727 hir::PatQPath(qself, lower_path(_lctx, pth))
729 PatStruct(ref pth, ref fields, etc) => {
730 let pth = lower_path(_lctx, pth);
731 let fs = fields.iter().map(|f| {
732 Spanned { span: f.span,
733 node: hir::FieldPat {
734 name: f.node.ident.name,
735 pat: lower_pat(_lctx, &f.node.pat),
736 is_shorthand: f.node.is_shorthand,
739 hir::PatStruct(pth, fs, etc)
741 PatTup(ref elts) => hir::PatTup(elts.iter().map(|x| lower_pat(_lctx, x)).collect()),
742 PatBox(ref inner) => hir::PatBox(lower_pat(_lctx, inner)),
743 PatRegion(ref inner, mutbl) => hir::PatRegion(lower_pat(_lctx, inner),
744 lower_mutability(_lctx, mutbl)),
745 PatRange(ref e1, ref e2) => {
746 hir::PatRange(lower_expr(_lctx, e1), lower_expr(_lctx, e2))
748 PatVec(ref before, ref slice, ref after) => {
749 hir::PatVec(before.iter().map(|x| lower_pat(_lctx, x)).collect(),
750 slice.as_ref().map(|x| lower_pat(_lctx, x)),
751 after.iter().map(|x| lower_pat(_lctx, x)).collect())
753 PatMac(_) => panic!("Shouldn't exist here"),
759 // RAII utility for setting and unsetting the cached id.
760 struct CachedIdSetter<'a> {
762 lctx: &'a LoweringContext<'a>,
765 impl<'a> CachedIdSetter<'a> {
766 fn new(lctx: &'a LoweringContext, expr_id: NodeId) -> CachedIdSetter<'a> {
767 let id_cache: &mut HashMap<_, _> = &mut lctx.id_cache.borrow_mut();
769 if id_cache.contains_key(&expr_id) {
770 let cached_id = lctx.cached_id.get();
772 // We're entering a node where we need to track ids, but are not
774 lctx.cached_id.set(id_cache[&expr_id]);
776 // We're already tracking - check that the tracked id is the same
777 // as the expected id.
778 assert!(cached_id == id_cache[&expr_id], "id mismatch");
781 id_cache.insert(expr_id, lctx.id_assigner.peek_node_id());
785 // Only reset the id if it was previously 0, i.e., was not cached.
786 // If it was cached, we are in a nested node, but our id count will
787 // still count towards the parent's count.
788 reset: lctx.cached_id.get() == 0,
794 impl<'a> Drop for CachedIdSetter<'a> {
797 self.lctx.cached_id.set(0);
802 pub fn lower_expr(lctx: &LoweringContext, e: &Expr) -> P<hir::Expr> {
807 // Eventually a desugaring for `box EXPR`
808 // (similar to the desugaring above for `in PLACE BLOCK`)
809 // should go here, desugaring
813 // let mut place = BoxPlace::make_place();
814 // let raw_place = Place::pointer(&mut place);
815 // let value = $value;
817 // ::std::ptr::write(raw_place, value);
818 // Boxed::finalize(place)
821 // But for now there are type-inference issues doing that.
823 hir::ExprBox(lower_expr(lctx, e))
826 // Desugar ExprBox: `in (PLACE) EXPR`
827 ExprInPlace(ref placer, ref value_expr) => {
831 // let mut place = Placer::make_place(p);
832 // let raw_place = Place::pointer(&mut place);
834 // std::intrinsics::move_val_init(raw_place, pop_unsafe!( EXPR ));
835 // InPlace::finalize(place)
837 let _old_cached = CachedIdSetter::new(lctx, e.id);
839 let placer_expr = lower_expr(lctx, placer);
840 let value_expr = lower_expr(lctx, value_expr);
842 let placer_ident = token::gensym_ident("placer");
843 let agent_ident = token::gensym_ident("place");
844 let p_ptr_ident = token::gensym_ident("p_ptr");
846 let make_place = ["ops", "Placer", "make_place"];
847 let place_pointer = ["ops", "Place", "pointer"];
848 let move_val_init = ["intrinsics", "move_val_init"];
849 let inplace_finalize = ["ops", "InPlace", "finalize"];
851 let make_call = |lctx, p, args| {
852 let path = core_path(lctx, e.span, p);
853 let path = expr_path(lctx, path);
854 expr_call(lctx, e.span, path, args)
857 let mk_stmt_let = |lctx, bind, expr| {
858 stmt_let(lctx, e.span, false, bind, expr)
860 let mk_stmt_let_mut = |lctx, bind, expr| {
861 stmt_let(lctx, e.span, true, bind, expr)
864 // let placer = <placer_expr> ;
865 let s1 = mk_stmt_let(lctx, placer_ident, placer_expr);
867 // let mut place = Placer::make_place(placer);
869 let call = make_call(lctx, &make_place, vec![expr_ident(lctx, e.span, placer_ident)]);
870 mk_stmt_let_mut(lctx, agent_ident, call)
873 // let p_ptr = Place::pointer(&mut place);
875 let args = vec![expr_mut_addr_of(lctx, e.span, expr_ident(lctx, e.span, agent_ident))];
876 let call = make_call(lctx, &place_pointer, args);
877 mk_stmt_let(lctx, p_ptr_ident, call)
880 // pop_unsafe!(EXPR));
881 let pop_unsafe_expr =
882 signal_block_expr(lctx,
884 signal_block_expr(lctx,
888 hir::PopUnstableBlock),
890 hir::PopUnsafeBlock(hir::CompilerGenerated));
893 // std::intrinsics::move_val_init(raw_place, pop_unsafe!( EXPR ));
894 // InPlace::finalize(place)
897 let call_move_val_init =
898 hir::StmtSemi(make_call(lctx,
900 vec![expr_ident(lctx, e.span, p_ptr_ident),
903 let call_move_val_init = respan(e.span, call_move_val_init);
905 let call = make_call(lctx, &inplace_finalize, vec![expr_ident(lctx, e.span, agent_ident)]);
906 signal_block_expr(lctx,
907 vec![P(call_move_val_init)],
910 hir::PushUnsafeBlock(hir::CompilerGenerated))
913 return signal_block_expr(lctx,
917 hir::PushUnstableBlock);
920 ExprVec(ref exprs) => {
921 hir::ExprVec(exprs.iter().map(|x| lower_expr(lctx, x)).collect())
923 ExprRepeat(ref expr, ref count) => {
924 hir::ExprRepeat(lower_expr(lctx, expr), lower_expr(lctx, count))
926 ExprTup(ref elts) => {
927 hir::ExprTup(elts.iter().map(|x| lower_expr(lctx, x)).collect())
929 ExprCall(ref f, ref args) => {
930 hir::ExprCall(lower_expr(lctx, f),
931 args.iter().map(|x| lower_expr(lctx, x)).collect())
933 ExprMethodCall(i, ref tps, ref args) => {
935 respan(i.span, i.node.name),
936 tps.iter().map(|x| lower_ty(lctx, x)).collect(),
937 args.iter().map(|x| lower_expr(lctx, x)).collect())
939 ExprBinary(binop, ref lhs, ref rhs) => {
940 hir::ExprBinary(lower_binop(lctx, binop),
941 lower_expr(lctx, lhs),
942 lower_expr(lctx, rhs))
944 ExprUnary(op, ref ohs) => {
945 hir::ExprUnary(lower_unop(lctx, op), lower_expr(lctx, ohs))
947 ExprLit(ref l) => hir::ExprLit(P((**l).clone())),
948 ExprCast(ref expr, ref ty) => {
949 hir::ExprCast(lower_expr(lctx, expr), lower_ty(lctx, ty))
951 ExprAddrOf(m, ref ohs) => {
952 hir::ExprAddrOf(lower_mutability(lctx, m), lower_expr(lctx, ohs))
954 // More complicated than you might expect because the else branch
955 // might be `if let`.
956 ExprIf(ref cond, ref blk, ref else_opt) => {
957 let else_opt = else_opt.as_ref().map(|els| match els.node {
959 let _old_cached = CachedIdSetter::new(lctx, e.id);
960 // wrap the if-let expr in a block
962 let blk = P(hir::Block {
964 expr: Some(lower_expr(lctx, els)),
966 rules: hir::DefaultBlock,
969 expr_block(lctx, blk)
971 _ => lower_expr(lctx, els)
974 hir::ExprIf(lower_expr(lctx, cond),
975 lower_block(lctx, blk),
978 ExprWhile(ref cond, ref body, opt_ident) => {
979 hir::ExprWhile(lower_expr(lctx, cond),
980 lower_block(lctx, body),
983 ExprLoop(ref body, opt_ident) => {
984 hir::ExprLoop(lower_block(lctx, body),
987 ExprMatch(ref expr, ref arms) => {
988 hir::ExprMatch(lower_expr(lctx, expr),
989 arms.iter().map(|x| lower_arm(lctx, x)).collect(),
990 hir::MatchSource::Normal)
992 ExprClosure(capture_clause, ref decl, ref body) => {
993 hir::ExprClosure(lower_capture_clause(lctx, capture_clause),
994 lower_fn_decl(lctx, decl),
995 lower_block(lctx, body))
997 ExprBlock(ref blk) => hir::ExprBlock(lower_block(lctx, blk)),
998 ExprAssign(ref el, ref er) => {
999 hir::ExprAssign(lower_expr(lctx, el), lower_expr(lctx, er))
1001 ExprAssignOp(op, ref el, ref er) => {
1002 hir::ExprAssignOp(lower_binop(lctx, op),
1003 lower_expr(lctx, el),
1004 lower_expr(lctx, er))
1006 ExprField(ref el, ident) => {
1007 hir::ExprField(lower_expr(lctx, el), respan(ident.span, ident.node.name))
1009 ExprTupField(ref el, ident) => {
1010 hir::ExprTupField(lower_expr(lctx, el), ident)
1012 ExprIndex(ref el, ref er) => {
1013 hir::ExprIndex(lower_expr(lctx, el), lower_expr(lctx, er))
1015 ExprRange(ref e1, ref e2) => {
1016 hir::ExprRange(e1.as_ref().map(|x| lower_expr(lctx, x)),
1017 e2.as_ref().map(|x| lower_expr(lctx, x)))
1019 ExprPath(ref qself, ref path) => {
1020 let qself = qself.as_ref().map(|&QSelf { ref ty, position }| {
1022 ty: lower_ty(lctx, ty),
1026 hir::ExprPath(qself, lower_path(lctx, path))
1028 ExprBreak(opt_ident) => hir::ExprBreak(opt_ident),
1029 ExprAgain(opt_ident) => hir::ExprAgain(opt_ident),
1030 ExprRet(ref e) => hir::ExprRet(e.as_ref().map(|x| lower_expr(lctx, x))),
1031 ExprInlineAsm(InlineAsm {
1041 }) => hir::ExprInlineAsm(hir::InlineAsm {
1042 inputs: inputs.iter().map(|&(ref c, ref input)| {
1043 (c.clone(), lower_expr(lctx, input))
1045 outputs: outputs.iter().map(|&(ref c, ref out, ref is_rw)| {
1046 (c.clone(), lower_expr(lctx, out), *is_rw)
1049 asm_str_style: asm_str_style,
1050 clobbers: clobbers.clone(),
1052 alignstack: alignstack,
1056 ExprStruct(ref path, ref fields, ref maybe_expr) => {
1057 hir::ExprStruct(lower_path(lctx, path),
1058 fields.iter().map(|x| lower_field(lctx, x)).collect(),
1059 maybe_expr.as_ref().map(|x| lower_expr(lctx, x)))
1061 ExprParen(ref ex) => {
1062 return lower_expr(lctx, ex);
1065 // Desugar ExprIfLet
1066 // From: `if let <pat> = <sub_expr> <body> [<else_opt>]`
1067 ExprIfLet(ref pat, ref sub_expr, ref body, ref else_opt) => {
1070 // match <sub_expr> {
1072 // [_ if <else_opt_if_cond> => <else_opt_if_body>,]
1073 // _ => [<else_opt> | ()]
1076 let _old_cached = CachedIdSetter::new(lctx, e.id);
1078 // `<pat> => <body>`
1080 let body_expr = expr_block(lctx, lower_block(lctx, body));
1081 arm(vec![lower_pat(lctx, pat)], body_expr)
1084 // `[_ if <else_opt_if_cond> => <else_opt_if_body>,]`
1085 let mut else_opt = else_opt.as_ref().map(|e| lower_expr(lctx, e));
1086 let else_if_arms = {
1087 let mut arms = vec![];
1089 let else_opt_continue = else_opt
1090 .and_then(|els| els.and_then(|els| match els.node {
1092 hir::ExprIf(cond, then, else_opt) => {
1093 let pat_under = pat_wild(lctx, e.span);
1094 arms.push(hir::Arm {
1096 pats: vec![pat_under],
1098 body: expr_block(lctx, then)
1100 else_opt.map(|else_opt| (else_opt, true))
1102 _ => Some((P(els), false))
1104 match else_opt_continue {
1105 Some((e, true)) => {
1108 Some((e, false)) => {
1121 let contains_else_clause = else_opt.is_some();
1123 // `_ => [<else_opt> | ()]`
1125 let pat_under = pat_wild(lctx, e.span);
1126 let else_expr = else_opt.unwrap_or_else(|| expr_tuple(lctx, e.span, vec![]));
1127 arm(vec![pat_under], else_expr)
1130 let mut arms = Vec::with_capacity(else_if_arms.len() + 2);
1132 arms.extend(else_if_arms);
1133 arms.push(else_arm);
1135 let match_expr = expr(lctx,
1137 hir::ExprMatch(lower_expr(lctx, sub_expr), arms,
1138 hir::MatchSource::IfLetDesugar {
1139 contains_else_clause: contains_else_clause,
1144 // Desugar ExprWhileLet
1145 // From: `[opt_ident]: while let <pat> = <sub_expr> <body>`
1146 ExprWhileLet(ref pat, ref sub_expr, ref body, opt_ident) => {
1149 // [opt_ident]: loop {
1150 // match <sub_expr> {
1156 let _old_cached = CachedIdSetter::new(lctx, e.id);
1158 // `<pat> => <body>`
1160 let body_expr = expr_block(lctx, lower_block(lctx, body));
1161 arm(vec![lower_pat(lctx, pat)], body_expr)
1166 let pat_under = pat_wild(lctx, e.span);
1167 let break_expr = expr_break(lctx, e.span);
1168 arm(vec![pat_under], break_expr)
1171 // // `match <sub_expr> { ... }`
1172 let arms = vec![pat_arm, break_arm];
1173 let match_expr = expr(lctx,
1175 hir::ExprMatch(lower_expr(lctx, sub_expr), arms, hir::MatchSource::WhileLetDesugar));
1177 // `[opt_ident]: loop { ... }`
1178 let loop_block = block_expr(lctx, match_expr);
1179 return expr(lctx, e.span, hir::ExprLoop(loop_block, opt_ident));
1182 // Desugar ExprForLoop
1183 // From: `[opt_ident]: for <pat> in <head> <body>`
1184 ExprForLoop(ref pat, ref head, ref body, opt_ident) => {
1188 // let result = match ::std::iter::IntoIterator::into_iter(<head>) {
1190 // [opt_ident]: loop {
1191 // match ::std::iter::Iterator::next(&mut iter) {
1192 // ::std::option::Option::Some(<pat>) => <body>,
1193 // ::std::option::Option::None => break
1201 let _old_cached = CachedIdSetter::new(lctx, e.id);
1204 let head = lower_expr(lctx, head);
1206 let iter = token::gensym_ident("iter");
1208 // `::std::option::Option::Some(<pat>) => <body>`
1210 let body_block = lower_block(lctx, body);
1211 let body_span = body_block.span;
1212 let body_expr = P(hir::Expr {
1214 node: hir::ExprBlock(body_block),
1217 let pat = lower_pat(lctx, pat);
1218 let some_pat = pat_some(lctx, e.span, pat);
1220 arm(vec![some_pat], body_expr)
1223 // `::std::option::Option::None => break`
1225 let break_expr = expr_break(lctx, e.span);
1227 arm(vec![pat_none(lctx, e.span)], break_expr)
1230 // `match ::std::iter::Iterator::next(&mut iter) { ... }`
1233 let strs = std_path(lctx, &["iter", "Iterator", "next"]);
1235 path_global(e.span, strs)
1237 let ref_mut_iter = expr_mut_addr_of(lctx, e.span, expr_ident(lctx, e.span, iter));
1239 expr_call(lctx, e.span, expr_path(lctx, next_path), vec![ref_mut_iter]);
1240 let arms = vec![pat_arm, break_arm];
1244 hir::ExprMatch(next_expr, arms, hir::MatchSource::ForLoopDesugar))
1247 // `[opt_ident]: loop { ... }`
1248 let loop_block = block_expr(lctx, match_expr);
1249 let loop_expr = expr(lctx, e.span, hir::ExprLoop(loop_block, opt_ident));
1251 // `mut iter => { ... }`
1254 pat_ident_binding_mode(lctx, e.span, iter, hir::BindByValue(hir::MutMutable));
1255 arm(vec![iter_pat], loop_expr)
1258 // `match ::std::iter::IntoIterator::into_iter(<head>) { ... }`
1259 let into_iter_expr = {
1260 let into_iter_path = {
1261 let strs = std_path(lctx, &["iter", "IntoIterator", "into_iter"]);
1263 path_global(e.span, strs)
1266 expr_call(lctx, e.span, expr_path(lctx, into_iter_path), vec![head])
1269 let match_expr = expr_match(lctx, e.span, into_iter_expr, vec![iter_arm]);
1271 // `{ let result = ...; result }`
1272 let result_ident = token::gensym_ident("result");
1273 return expr_block(lctx,
1276 vec![stmt_let(lctx, e.span,
1280 Some(expr_ident(lctx, e.span, result_ident))))
1283 ExprMac(_) => panic!("Shouldn't exist here"),
1289 pub fn lower_stmt(_lctx: &LoweringContext, s: &Stmt) -> P<hir::Stmt> {
1291 StmtDecl(ref d, id) => {
1293 node: hir::StmtDecl(lower_decl(_lctx, d), id),
1297 StmtExpr(ref e, id) => {
1299 node: hir::StmtExpr(lower_expr(_lctx, e), id),
1303 StmtSemi(ref e, id) => {
1305 node: hir::StmtSemi(lower_expr(_lctx, e), id),
1309 StmtMac(..) => panic!("Shouldn't exist here"),
1313 pub fn lower_capture_clause(_lctx: &LoweringContext, c: CaptureClause) -> hir::CaptureClause {
1315 CaptureByValue => hir::CaptureByValue,
1316 CaptureByRef => hir::CaptureByRef,
1320 pub fn lower_visibility(_lctx: &LoweringContext, v: Visibility) -> hir::Visibility {
1322 Public => hir::Public,
1323 Inherited => hir::Inherited,
1327 pub fn lower_block_check_mode(_lctx: &LoweringContext, b: &BlockCheckMode) -> hir::BlockCheckMode {
1329 DefaultBlock => hir::DefaultBlock,
1330 UnsafeBlock(u) => hir::UnsafeBlock(lower_unsafe_source(_lctx, u)),
1331 PushUnsafeBlock(u) => hir::PushUnsafeBlock(lower_unsafe_source(_lctx, u)),
1332 PopUnsafeBlock(u) => hir::PopUnsafeBlock(lower_unsafe_source(_lctx, u)),
1336 pub fn lower_pat_wild_kind(_lctx: &LoweringContext, p: PatWildKind) -> hir::PatWildKind {
1338 PatWildSingle => hir::PatWildSingle,
1339 PatWildMulti => hir::PatWildMulti,
1343 pub fn lower_binding_mode(_lctx: &LoweringContext, b: &BindingMode) -> hir::BindingMode {
1345 BindByRef(m) => hir::BindByRef(lower_mutability(_lctx, m)),
1346 BindByValue(m) => hir::BindByValue(lower_mutability(_lctx, m)),
1350 pub fn lower_struct_field_kind(_lctx: &LoweringContext,
1351 s: &StructFieldKind)
1352 -> hir::StructFieldKind {
1354 NamedField(ident, vis) => hir::NamedField(ident.name, lower_visibility(_lctx, vis)),
1355 UnnamedField(vis) => hir::UnnamedField(lower_visibility(_lctx, vis)),
1359 pub fn lower_unsafe_source(_lctx: &LoweringContext, u: UnsafeSource) -> hir::UnsafeSource {
1361 CompilerGenerated => hir::CompilerGenerated,
1362 UserProvided => hir::UserProvided,
1366 pub fn lower_impl_polarity(_lctx: &LoweringContext, i: ImplPolarity) -> hir::ImplPolarity {
1368 ImplPolarity::Positive => hir::ImplPolarity::Positive,
1369 ImplPolarity::Negative => hir::ImplPolarity::Negative,
1373 pub fn lower_trait_bound_modifier(_lctx: &LoweringContext,
1374 f: TraitBoundModifier)
1375 -> hir::TraitBoundModifier {
1377 TraitBoundModifier::None => hir::TraitBoundModifier::None,
1378 TraitBoundModifier::Maybe => hir::TraitBoundModifier::Maybe,
1382 // Helper methods for building HIR.
1384 fn arm(pats: Vec<P<hir::Pat>>, expr: P<hir::Expr>) -> hir::Arm {
1393 fn expr_break(lctx: &LoweringContext, span: Span) -> P<hir::Expr> {
1394 expr(lctx, span, hir::ExprBreak(None))
1397 fn expr_call(lctx: &LoweringContext, span: Span, e: P<hir::Expr>, args: Vec<P<hir::Expr>>) -> P<hir::Expr> {
1398 expr(lctx, span, hir::ExprCall(e, args))
1401 fn expr_ident(lctx: &LoweringContext, span: Span, id: Ident) -> P<hir::Expr> {
1402 expr_path(lctx, path_ident(span, id))
1405 fn expr_mut_addr_of(lctx: &LoweringContext, span: Span, e: P<hir::Expr>) -> P<hir::Expr> {
1406 expr(lctx, span, hir::ExprAddrOf(hir::MutMutable, e))
1409 fn expr_path(lctx: &LoweringContext, path: hir::Path) -> P<hir::Expr> {
1410 expr(lctx, path.span, hir::ExprPath(None, path))
1413 fn expr_match(lctx: &LoweringContext, span: Span, arg: P<hir::Expr>, arms: Vec<hir::Arm>) -> P<hir::Expr> {
1414 expr(lctx, span, hir::ExprMatch(arg, arms, hir::MatchSource::Normal))
1417 fn expr_block(lctx: &LoweringContext, b: P<hir::Block>) -> P<hir::Expr> {
1418 expr(lctx, b.span, hir::ExprBlock(b))
1421 fn expr_tuple(lctx: &LoweringContext, sp: Span, exprs: Vec<P<hir::Expr>>) -> P<hir::Expr> {
1422 expr(lctx, sp, hir::ExprTup(exprs))
1425 fn expr(lctx: &LoweringContext, span: Span, node: hir::Expr_) -> P<hir::Expr> {
1433 fn stmt_let(lctx: &LoweringContext, sp: Span, mutbl: bool, ident: Ident, ex: P<hir::Expr>) -> P<hir::Stmt> {
1434 let pat = if mutbl {
1435 pat_ident_binding_mode(lctx, sp, ident, hir::BindByValue(hir::MutMutable))
1437 pat_ident(lctx, sp, ident)
1439 let local = P(hir::Local {
1446 let decl = respan(sp, hir::DeclLocal(local));
1447 P(respan(sp, hir::StmtDecl(P(decl), lctx.next_id())))
1450 fn block_expr(lctx: &LoweringContext, expr: P<hir::Expr>) -> P<hir::Block> {
1451 block_all(lctx, expr.span, Vec::new(), Some(expr))
1454 fn block_all(lctx: &LoweringContext,
1456 stmts: Vec<P<hir::Stmt>>,
1457 expr: Option<P<hir::Expr>>) -> P<hir::Block> {
1462 rules: hir::DefaultBlock,
1467 fn pat_some(lctx: &LoweringContext, span: Span, pat: P<hir::Pat>) -> P<hir::Pat> {
1468 let some = std_path(lctx, &["option", "Option", "Some"]);
1469 let path = path_global(span, some);
1470 pat_enum(lctx, span, path, vec!(pat))
1473 fn pat_none(lctx: &LoweringContext, span: Span) -> P<hir::Pat> {
1474 let none = std_path(lctx, &["option", "Option", "None"]);
1475 let path = path_global(span, none);
1476 pat_enum(lctx, span, path, vec![])
1479 fn pat_enum(lctx: &LoweringContext, span: Span, path: hir::Path, subpats: Vec<P<hir::Pat>>) -> P<hir::Pat> {
1480 let pt = hir::PatEnum(path, Some(subpats));
1484 fn pat_ident(lctx: &LoweringContext, span: Span, ident: Ident) -> P<hir::Pat> {
1485 pat_ident_binding_mode(lctx, span, ident, hir::BindByValue(hir::MutImmutable))
1488 fn pat_ident_binding_mode(lctx: &LoweringContext,
1491 bm: hir::BindingMode) -> P<hir::Pat> {
1492 let pat_ident = hir::PatIdent(bm, Spanned{span: span, node: ident}, None);
1493 pat(lctx, span, pat_ident)
1496 fn pat_wild(lctx: &LoweringContext, span: Span) -> P<hir::Pat> {
1497 pat(lctx, span, hir::PatWild(hir::PatWildSingle))
1500 fn pat(lctx: &LoweringContext, span: Span, pat: hir::Pat_) -> P<hir::Pat> {
1501 P(hir::Pat { id: lctx.next_id(), node: pat, span: span })
1504 fn path_ident(span: Span, id: Ident) -> hir::Path {
1505 path(span, vec!(id))
1508 fn path(span: Span, strs: Vec<Ident> ) -> hir::Path {
1509 path_all(span, false, strs, Vec::new(), Vec::new(), Vec::new())
1512 fn path_global(span: Span, strs: Vec<Ident> ) -> hir::Path {
1513 path_all(span, true, strs, Vec::new(), Vec::new(), Vec::new())
1516 fn path_all(sp: Span,
1518 mut idents: Vec<Ident> ,
1519 lifetimes: Vec<hir::Lifetime>,
1520 types: Vec<P<hir::Ty>>,
1521 bindings: Vec<P<hir::TypeBinding>> )
1523 let last_identifier = idents.pop().unwrap();
1524 let mut segments: Vec<hir::PathSegment> = idents.into_iter()
1528 parameters: hir::PathParameters::none(),
1531 segments.push(hir::PathSegment {
1532 identifier: last_identifier,
1533 parameters: hir::AngleBracketedParameters(hir::AngleBracketedParameterData {
1534 lifetimes: lifetimes,
1535 types: OwnedSlice::from_vec(types),
1536 bindings: OwnedSlice::from_vec(bindings),
1546 fn std_path(lctx: &LoweringContext, components: &[&str]) -> Vec<Ident> {
1547 let mut v = Vec::new();
1548 if let Some(s) = lctx.crate_root {
1549 v.push(str_to_ident(s));
1551 v.extend(components.iter().map(|s| str_to_ident(s)));
1555 // Given suffix ["b","c","d"], returns path `::std::b::c::d` when
1556 // `fld.cx.use_std`, and `::core::b::c::d` otherwise.
1557 fn core_path(lctx: &LoweringContext, span: Span, components: &[&str]) -> hir::Path {
1558 let idents = std_path(lctx, components);
1559 path_global(span, idents)
1562 fn signal_block_expr(lctx: &LoweringContext, stmts: Vec<P<hir::Stmt>>, expr: P<hir::Expr>, span: Span, rule: hir::BlockCheckMode) -> P<hir::Expr> {
1563 expr_block(lctx, P(hir::Block {
1564 rules: rule, span: span, id: lctx.next_id(),
1565 stmts: stmts, expr: Some(expr),