rustc_middle/ty/
adt.rs

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1use std::cell::RefCell;
2use std::hash::{Hash, Hasher};
3use std::ops::Range;
4use std::str;
5
6use rustc_abi::{FIRST_VARIANT, ReprOptions, VariantIdx};
7use rustc_data_structures::fingerprint::Fingerprint;
8use rustc_data_structures::fx::FxHashMap;
9use rustc_data_structures::intern::Interned;
10use rustc_data_structures::stable_hasher::{HashStable, HashingControls, StableHasher};
11use rustc_errors::ErrorGuaranteed;
12use rustc_hir::def::{CtorKind, DefKind, Res};
13use rustc_hir::def_id::DefId;
14use rustc_hir::{self as hir, LangItem};
15use rustc_index::{IndexSlice, IndexVec};
16use rustc_macros::{HashStable, TyDecodable, TyEncodable};
17use rustc_query_system::ich::StableHashingContext;
18use rustc_session::DataTypeKind;
19use rustc_span::sym;
20use rustc_type_ir::solve::AdtDestructorKind;
21use tracing::{debug, info, trace};
22
23use super::{
24    AsyncDestructor, Destructor, FieldDef, GenericPredicates, Ty, TyCtxt, VariantDef, VariantDiscr,
25};
26use crate::mir::interpret::ErrorHandled;
27use crate::ty;
28use crate::ty::util::{Discr, IntTypeExt};
29
30#[derive(Clone, Copy, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
31pub struct AdtFlags(u16);
32bitflags::bitflags! {
33    impl AdtFlags: u16 {
34        const NO_ADT_FLAGS        = 0;
35        /// Indicates whether the ADT is an enum.
36        const IS_ENUM             = 1 << 0;
37        /// Indicates whether the ADT is a union.
38        const IS_UNION            = 1 << 1;
39        /// Indicates whether the ADT is a struct.
40        const IS_STRUCT           = 1 << 2;
41        /// Indicates whether the ADT is a struct and has a constructor.
42        const HAS_CTOR            = 1 << 3;
43        /// Indicates whether the type is `PhantomData`.
44        const IS_PHANTOM_DATA     = 1 << 4;
45        /// Indicates whether the type has a `#[fundamental]` attribute.
46        const IS_FUNDAMENTAL      = 1 << 5;
47        /// Indicates whether the type is `Box`.
48        const IS_BOX              = 1 << 6;
49        /// Indicates whether the type is `ManuallyDrop`.
50        const IS_MANUALLY_DROP    = 1 << 7;
51        /// Indicates whether the variant list of this ADT is `#[non_exhaustive]`.
52        /// (i.e., this flag is never set unless this ADT is an enum).
53        const IS_VARIANT_LIST_NON_EXHAUSTIVE = 1 << 8;
54        /// Indicates whether the type is `UnsafeCell`.
55        const IS_UNSAFE_CELL              = 1 << 9;
56    }
57}
58rustc_data_structures::external_bitflags_debug! { AdtFlags }
59
60/// The definition of a user-defined type, e.g., a `struct`, `enum`, or `union`.
61///
62/// These are all interned (by `mk_adt_def`) into the global arena.
63///
64/// The initialism *ADT* stands for an [*algebraic data type (ADT)*][adt].
65/// This is slightly wrong because `union`s are not ADTs.
66/// Moreover, Rust only allows recursive data types through indirection.
67///
68/// [adt]: https://en.wikipedia.org/wiki/Algebraic_data_type
69///
70/// # Recursive types
71///
72/// It may seem impossible to represent recursive types using [`Ty`],
73/// since [`TyKind::Adt`] includes [`AdtDef`], which includes its fields,
74/// creating a cycle. However, `AdtDef` does not actually include the *types*
75/// of its fields; it includes just their [`DefId`]s.
76///
77/// [`TyKind::Adt`]: ty::TyKind::Adt
78///
79/// For example, the following type:
80///
81/// ```
82/// struct S { x: Box<S> }
83/// ```
84///
85/// is essentially represented with [`Ty`] as the following pseudocode:
86///
87/// ```ignore (illustrative)
88/// struct S { x }
89/// ```
90///
91/// where `x` here represents the `DefId` of `S.x`. Then, the `DefId`
92/// can be used with [`TyCtxt::type_of()`] to get the type of the field.
93#[derive(TyEncodable, TyDecodable)]
94pub struct AdtDefData {
95    /// The `DefId` of the struct, enum or union item.
96    pub did: DefId,
97    /// Variants of the ADT. If this is a struct or union, then there will be a single variant.
98    variants: IndexVec<VariantIdx, VariantDef>,
99    /// Flags of the ADT (e.g., is this a struct? is this non-exhaustive?).
100    flags: AdtFlags,
101    /// Repr options provided by the user.
102    repr: ReprOptions,
103}
104
105impl PartialEq for AdtDefData {
106    #[inline]
107    fn eq(&self, other: &Self) -> bool {
108        // There should be only one `AdtDefData` for each `def_id`, therefore
109        // it is fine to implement `PartialEq` only based on `def_id`.
110        //
111        // Below, we exhaustively destructure `self` and `other` so that if the
112        // definition of `AdtDefData` changes, a compile-error will be produced,
113        // reminding us to revisit this assumption.
114
115        let Self { did: self_def_id, variants: _, flags: _, repr: _ } = self;
116        let Self { did: other_def_id, variants: _, flags: _, repr: _ } = other;
117
118        let res = self_def_id == other_def_id;
119
120        // Double check that implicit assumption detailed above.
121        if cfg!(debug_assertions) && res {
122            let deep = self.flags == other.flags
123                && self.repr == other.repr
124                && self.variants == other.variants;
125            assert!(deep, "AdtDefData for the same def-id has differing data");
126        }
127
128        res
129    }
130}
131
132impl Eq for AdtDefData {}
133
134/// There should be only one AdtDef for each `did`, therefore
135/// it is fine to implement `Hash` only based on `did`.
136impl Hash for AdtDefData {
137    #[inline]
138    fn hash<H: Hasher>(&self, s: &mut H) {
139        self.did.hash(s)
140    }
141}
142
143impl<'a> HashStable<StableHashingContext<'a>> for AdtDefData {
144    fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
145        thread_local! {
146            static CACHE: RefCell<FxHashMap<(usize, HashingControls), Fingerprint>> = Default::default();
147        }
148
149        let hash: Fingerprint = CACHE.with(|cache| {
150            let addr = self as *const AdtDefData as usize;
151            let hashing_controls = hcx.hashing_controls();
152            *cache.borrow_mut().entry((addr, hashing_controls)).or_insert_with(|| {
153                let ty::AdtDefData { did, ref variants, ref flags, ref repr } = *self;
154
155                let mut hasher = StableHasher::new();
156                did.hash_stable(hcx, &mut hasher);
157                variants.hash_stable(hcx, &mut hasher);
158                flags.hash_stable(hcx, &mut hasher);
159                repr.hash_stable(hcx, &mut hasher);
160
161                hasher.finish()
162            })
163        });
164
165        hash.hash_stable(hcx, hasher);
166    }
167}
168
169#[derive(Copy, Clone, PartialEq, Eq, Hash, HashStable)]
170#[rustc_pass_by_value]
171pub struct AdtDef<'tcx>(pub Interned<'tcx, AdtDefData>);
172
173impl<'tcx> AdtDef<'tcx> {
174    #[inline]
175    pub fn did(self) -> DefId {
176        self.0.0.did
177    }
178
179    #[inline]
180    pub fn variants(self) -> &'tcx IndexSlice<VariantIdx, VariantDef> {
181        &self.0.0.variants
182    }
183
184    #[inline]
185    pub fn variant(self, idx: VariantIdx) -> &'tcx VariantDef {
186        &self.0.0.variants[idx]
187    }
188
189    #[inline]
190    pub fn flags(self) -> AdtFlags {
191        self.0.0.flags
192    }
193
194    #[inline]
195    pub fn repr(self) -> ReprOptions {
196        self.0.0.repr
197    }
198}
199
200impl<'tcx> rustc_type_ir::inherent::AdtDef<TyCtxt<'tcx>> for AdtDef<'tcx> {
201    fn def_id(self) -> DefId {
202        self.did()
203    }
204
205    fn is_struct(self) -> bool {
206        self.is_struct()
207    }
208
209    fn struct_tail_ty(self, interner: TyCtxt<'tcx>) -> Option<ty::EarlyBinder<'tcx, Ty<'tcx>>> {
210        Some(interner.type_of(self.non_enum_variant().tail_opt()?.did))
211    }
212
213    fn is_phantom_data(self) -> bool {
214        self.is_phantom_data()
215    }
216
217    fn is_manually_drop(self) -> bool {
218        self.is_manually_drop()
219    }
220
221    fn all_field_tys(
222        self,
223        tcx: TyCtxt<'tcx>,
224    ) -> ty::EarlyBinder<'tcx, impl IntoIterator<Item = Ty<'tcx>>> {
225        ty::EarlyBinder::bind(
226            self.all_fields().map(move |field| tcx.type_of(field.did).skip_binder()),
227        )
228    }
229
230    fn sized_constraint(self, tcx: TyCtxt<'tcx>) -> Option<ty::EarlyBinder<'tcx, Ty<'tcx>>> {
231        self.sized_constraint(tcx)
232    }
233
234    fn is_fundamental(self) -> bool {
235        self.is_fundamental()
236    }
237
238    fn destructor(self, tcx: TyCtxt<'tcx>) -> Option<AdtDestructorKind> {
239        Some(match self.destructor(tcx)?.constness {
240            hir::Constness::Const => AdtDestructorKind::Const,
241            hir::Constness::NotConst => AdtDestructorKind::NotConst,
242        })
243    }
244}
245
246#[derive(Copy, Clone, Debug, Eq, PartialEq, HashStable, TyEncodable, TyDecodable)]
247pub enum AdtKind {
248    Struct,
249    Union,
250    Enum,
251}
252
253impl From<AdtKind> for DataTypeKind {
254    fn from(val: AdtKind) -> Self {
255        match val {
256            AdtKind::Struct => DataTypeKind::Struct,
257            AdtKind::Union => DataTypeKind::Union,
258            AdtKind::Enum => DataTypeKind::Enum,
259        }
260    }
261}
262
263impl AdtDefData {
264    /// Creates a new `AdtDefData`.
265    pub(super) fn new(
266        tcx: TyCtxt<'_>,
267        did: DefId,
268        kind: AdtKind,
269        variants: IndexVec<VariantIdx, VariantDef>,
270        repr: ReprOptions,
271    ) -> Self {
272        debug!("AdtDef::new({:?}, {:?}, {:?}, {:?})", did, kind, variants, repr);
273        let mut flags = AdtFlags::NO_ADT_FLAGS;
274
275        if kind == AdtKind::Enum && tcx.has_attr(did, sym::non_exhaustive) {
276            debug!("found non-exhaustive variant list for {:?}", did);
277            flags = flags | AdtFlags::IS_VARIANT_LIST_NON_EXHAUSTIVE;
278        }
279
280        flags |= match kind {
281            AdtKind::Enum => AdtFlags::IS_ENUM,
282            AdtKind::Union => AdtFlags::IS_UNION,
283            AdtKind::Struct => AdtFlags::IS_STRUCT,
284        };
285
286        if kind == AdtKind::Struct && variants[FIRST_VARIANT].ctor.is_some() {
287            flags |= AdtFlags::HAS_CTOR;
288        }
289
290        if tcx.has_attr(did, sym::fundamental) {
291            flags |= AdtFlags::IS_FUNDAMENTAL;
292        }
293        if tcx.is_lang_item(did, LangItem::PhantomData) {
294            flags |= AdtFlags::IS_PHANTOM_DATA;
295        }
296        if tcx.is_lang_item(did, LangItem::OwnedBox) {
297            flags |= AdtFlags::IS_BOX;
298        }
299        if tcx.is_lang_item(did, LangItem::ManuallyDrop) {
300            flags |= AdtFlags::IS_MANUALLY_DROP;
301        }
302        if tcx.is_lang_item(did, LangItem::UnsafeCell) {
303            flags |= AdtFlags::IS_UNSAFE_CELL;
304        }
305
306        AdtDefData { did, variants, flags, repr }
307    }
308}
309
310impl<'tcx> AdtDef<'tcx> {
311    /// Returns `true` if this is a struct.
312    #[inline]
313    pub fn is_struct(self) -> bool {
314        self.flags().contains(AdtFlags::IS_STRUCT)
315    }
316
317    /// Returns `true` if this is a union.
318    #[inline]
319    pub fn is_union(self) -> bool {
320        self.flags().contains(AdtFlags::IS_UNION)
321    }
322
323    /// Returns `true` if this is an enum.
324    #[inline]
325    pub fn is_enum(self) -> bool {
326        self.flags().contains(AdtFlags::IS_ENUM)
327    }
328
329    /// Returns `true` if the variant list of this ADT is `#[non_exhaustive]`.
330    ///
331    /// Note that this function will return `true` even if the ADT has been
332    /// defined in the crate currently being compiled. If that's not what you
333    /// want, see [`Self::variant_list_has_applicable_non_exhaustive`].
334    #[inline]
335    pub fn is_variant_list_non_exhaustive(self) -> bool {
336        self.flags().contains(AdtFlags::IS_VARIANT_LIST_NON_EXHAUSTIVE)
337    }
338
339    /// Returns `true` if the variant list of this ADT is `#[non_exhaustive]`
340    /// and has been defined in another crate.
341    #[inline]
342    pub fn variant_list_has_applicable_non_exhaustive(self) -> bool {
343        self.is_variant_list_non_exhaustive() && !self.did().is_local()
344    }
345
346    /// Returns the kind of the ADT.
347    #[inline]
348    pub fn adt_kind(self) -> AdtKind {
349        if self.is_enum() {
350            AdtKind::Enum
351        } else if self.is_union() {
352            AdtKind::Union
353        } else {
354            AdtKind::Struct
355        }
356    }
357
358    /// Returns a description of this abstract data type.
359    pub fn descr(self) -> &'static str {
360        match self.adt_kind() {
361            AdtKind::Struct => "struct",
362            AdtKind::Union => "union",
363            AdtKind::Enum => "enum",
364        }
365    }
366
367    /// Returns a description of a variant of this abstract data type.
368    #[inline]
369    pub fn variant_descr(self) -> &'static str {
370        match self.adt_kind() {
371            AdtKind::Struct => "struct",
372            AdtKind::Union => "union",
373            AdtKind::Enum => "variant",
374        }
375    }
376
377    /// If this function returns `true`, it implies that `is_struct` must return `true`.
378    #[inline]
379    pub fn has_ctor(self) -> bool {
380        self.flags().contains(AdtFlags::HAS_CTOR)
381    }
382
383    /// Returns `true` if this type is `#[fundamental]` for the purposes
384    /// of coherence checking.
385    #[inline]
386    pub fn is_fundamental(self) -> bool {
387        self.flags().contains(AdtFlags::IS_FUNDAMENTAL)
388    }
389
390    /// Returns `true` if this is `PhantomData<T>`.
391    #[inline]
392    pub fn is_phantom_data(self) -> bool {
393        self.flags().contains(AdtFlags::IS_PHANTOM_DATA)
394    }
395
396    /// Returns `true` if this is `Box<T>`.
397    #[inline]
398    pub fn is_box(self) -> bool {
399        self.flags().contains(AdtFlags::IS_BOX)
400    }
401
402    /// Returns `true` if this is `UnsafeCell<T>`.
403    #[inline]
404    pub fn is_unsafe_cell(self) -> bool {
405        self.flags().contains(AdtFlags::IS_UNSAFE_CELL)
406    }
407
408    /// Returns `true` if this is `ManuallyDrop<T>`.
409    #[inline]
410    pub fn is_manually_drop(self) -> bool {
411        self.flags().contains(AdtFlags::IS_MANUALLY_DROP)
412    }
413
414    /// Returns `true` if this type has a destructor.
415    pub fn has_dtor(self, tcx: TyCtxt<'tcx>) -> bool {
416        self.destructor(tcx).is_some()
417    }
418
419    /// Asserts this is a struct or union and returns its unique variant.
420    pub fn non_enum_variant(self) -> &'tcx VariantDef {
421        assert!(self.is_struct() || self.is_union());
422        self.variant(FIRST_VARIANT)
423    }
424
425    #[inline]
426    pub fn predicates(self, tcx: TyCtxt<'tcx>) -> GenericPredicates<'tcx> {
427        tcx.predicates_of(self.did())
428    }
429
430    /// Returns an iterator over all fields contained
431    /// by this ADT (nested unnamed fields are not expanded).
432    #[inline]
433    pub fn all_fields(self) -> impl Iterator<Item = &'tcx FieldDef> + Clone {
434        self.variants().iter().flat_map(|v| v.fields.iter())
435    }
436
437    /// Whether the ADT lacks fields. Note that this includes uninhabited enums,
438    /// e.g., `enum Void {}` is considered payload free as well.
439    pub fn is_payloadfree(self) -> bool {
440        // Treat the ADT as not payload-free if arbitrary_enum_discriminant is used (#88621).
441        // This would disallow the following kind of enum from being casted into integer.
442        // ```
443        // enum Enum {
444        //    Foo() = 1,
445        //    Bar{} = 2,
446        //    Baz = 3,
447        // }
448        // ```
449        if self.variants().iter().any(|v| {
450            matches!(v.discr, VariantDiscr::Explicit(_)) && v.ctor_kind() != Some(CtorKind::Const)
451        }) {
452            return false;
453        }
454        self.variants().iter().all(|v| v.fields.is_empty())
455    }
456
457    /// Return a `VariantDef` given a variant id.
458    pub fn variant_with_id(self, vid: DefId) -> &'tcx VariantDef {
459        self.variants().iter().find(|v| v.def_id == vid).expect("variant_with_id: unknown variant")
460    }
461
462    /// Return a `VariantDef` given a constructor id.
463    pub fn variant_with_ctor_id(self, cid: DefId) -> &'tcx VariantDef {
464        self.variants()
465            .iter()
466            .find(|v| v.ctor_def_id() == Some(cid))
467            .expect("variant_with_ctor_id: unknown variant")
468    }
469
470    /// Return the index of `VariantDef` given a variant id.
471    #[inline]
472    pub fn variant_index_with_id(self, vid: DefId) -> VariantIdx {
473        self.variants()
474            .iter_enumerated()
475            .find(|(_, v)| v.def_id == vid)
476            .expect("variant_index_with_id: unknown variant")
477            .0
478    }
479
480    /// Return the index of `VariantDef` given a constructor id.
481    pub fn variant_index_with_ctor_id(self, cid: DefId) -> VariantIdx {
482        self.variants()
483            .iter_enumerated()
484            .find(|(_, v)| v.ctor_def_id() == Some(cid))
485            .expect("variant_index_with_ctor_id: unknown variant")
486            .0
487    }
488
489    pub fn variant_of_res(self, res: Res) -> &'tcx VariantDef {
490        match res {
491            Res::Def(DefKind::Variant, vid) => self.variant_with_id(vid),
492            Res::Def(DefKind::Ctor(..), cid) => self.variant_with_ctor_id(cid),
493            Res::Def(DefKind::Struct, _)
494            | Res::Def(DefKind::Union, _)
495            | Res::Def(DefKind::TyAlias, _)
496            | Res::Def(DefKind::AssocTy, _)
497            | Res::SelfTyParam { .. }
498            | Res::SelfTyAlias { .. }
499            | Res::SelfCtor(..) => self.non_enum_variant(),
500            _ => bug!("unexpected res {:?} in variant_of_res", res),
501        }
502    }
503
504    #[inline]
505    pub fn eval_explicit_discr(
506        self,
507        tcx: TyCtxt<'tcx>,
508        expr_did: DefId,
509    ) -> Result<Discr<'tcx>, ErrorGuaranteed> {
510        assert!(self.is_enum());
511
512        let repr_type = self.repr().discr_type();
513        match tcx.const_eval_poly(expr_did) {
514            Ok(val) => {
515                let typing_env = ty::TypingEnv::post_analysis(tcx, expr_did);
516                let ty = repr_type.to_ty(tcx);
517                if let Some(b) = val.try_to_bits_for_ty(tcx, typing_env, ty) {
518                    trace!("discriminants: {} ({:?})", b, repr_type);
519                    Ok(Discr { val: b, ty })
520                } else {
521                    info!("invalid enum discriminant: {:#?}", val);
522                    let guar = tcx.dcx().emit_err(crate::error::ConstEvalNonIntError {
523                        span: tcx.def_span(expr_did),
524                    });
525                    Err(guar)
526                }
527            }
528            Err(err) => {
529                let guar = match err {
530                    ErrorHandled::Reported(info, _) => info.into(),
531                    ErrorHandled::TooGeneric(..) => tcx.dcx().span_delayed_bug(
532                        tcx.def_span(expr_did),
533                        "enum discriminant depends on generics",
534                    ),
535                };
536                Err(guar)
537            }
538        }
539    }
540
541    #[inline]
542    pub fn discriminants(
543        self,
544        tcx: TyCtxt<'tcx>,
545    ) -> impl Iterator<Item = (VariantIdx, Discr<'tcx>)> {
546        assert!(self.is_enum());
547        let repr_type = self.repr().discr_type();
548        let initial = repr_type.initial_discriminant(tcx);
549        let mut prev_discr = None::<Discr<'tcx>>;
550        self.variants().iter_enumerated().map(move |(i, v)| {
551            let mut discr = prev_discr.map_or(initial, |d| d.wrap_incr(tcx));
552            if let VariantDiscr::Explicit(expr_did) = v.discr {
553                if let Ok(new_discr) = self.eval_explicit_discr(tcx, expr_did) {
554                    discr = new_discr;
555                }
556            }
557            prev_discr = Some(discr);
558
559            (i, discr)
560        })
561    }
562
563    #[inline]
564    pub fn variant_range(self) -> Range<VariantIdx> {
565        FIRST_VARIANT..self.variants().next_index()
566    }
567
568    /// Computes the discriminant value used by a specific variant.
569    /// Unlike `discriminants`, this is (amortized) constant-time,
570    /// only doing at most one query for evaluating an explicit
571    /// discriminant (the last one before the requested variant),
572    /// assuming there are no constant-evaluation errors there.
573    #[inline]
574    pub fn discriminant_for_variant(
575        self,
576        tcx: TyCtxt<'tcx>,
577        variant_index: VariantIdx,
578    ) -> Discr<'tcx> {
579        assert!(self.is_enum());
580        let (val, offset) = self.discriminant_def_for_variant(variant_index);
581        let explicit_value = if let Some(expr_did) = val
582            && let Ok(val) = self.eval_explicit_discr(tcx, expr_did)
583        {
584            val
585        } else {
586            self.repr().discr_type().initial_discriminant(tcx)
587        };
588        explicit_value.checked_add(tcx, offset as u128).0
589    }
590
591    /// Yields a `DefId` for the discriminant and an offset to add to it
592    /// Alternatively, if there is no explicit discriminant, returns the
593    /// inferred discriminant directly.
594    pub fn discriminant_def_for_variant(self, variant_index: VariantIdx) -> (Option<DefId>, u32) {
595        assert!(!self.variants().is_empty());
596        let mut explicit_index = variant_index.as_u32();
597        let expr_did;
598        loop {
599            match self.variant(VariantIdx::from_u32(explicit_index)).discr {
600                ty::VariantDiscr::Relative(0) => {
601                    expr_did = None;
602                    break;
603                }
604                ty::VariantDiscr::Relative(distance) => {
605                    explicit_index -= distance;
606                }
607                ty::VariantDiscr::Explicit(did) => {
608                    expr_did = Some(did);
609                    break;
610                }
611            }
612        }
613        (expr_did, variant_index.as_u32() - explicit_index)
614    }
615
616    pub fn destructor(self, tcx: TyCtxt<'tcx>) -> Option<Destructor> {
617        tcx.adt_destructor(self.did())
618    }
619
620    // FIXME: consider combining this method with `AdtDef::destructor` and removing
621    // this version
622    pub fn async_destructor(self, tcx: TyCtxt<'tcx>) -> Option<AsyncDestructor> {
623        tcx.adt_async_destructor(self.did())
624    }
625
626    /// Returns a type such that `Self: Sized` if and only if that type is `Sized`,
627    /// or `None` if the type is always sized.
628    pub fn sized_constraint(self, tcx: TyCtxt<'tcx>) -> Option<ty::EarlyBinder<'tcx, Ty<'tcx>>> {
629        if self.is_struct() { tcx.adt_sized_constraint(self.did()) } else { None }
630    }
631}
632
633#[derive(Clone, Copy, Debug, HashStable)]
634pub enum Representability {
635    Representable,
636    Infinite(ErrorGuaranteed),
637}
rustc_middle/ty/adt.rs

rustc_middle/ty/
adt.rs
