Create rustc_ty_library
This commit is contained in:
parent
a094ff9590
commit
0cf5a8ad15
11
Cargo.lock
11
Cargo.lock
@ -3918,6 +3918,7 @@ dependencies = [
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"rustc_session",
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"rustc_span",
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"rustc_target",
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"rustc_type_ir",
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"smallvec 1.4.2",
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"tracing",
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]
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@ -4251,6 +4252,16 @@ dependencies = [
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"tracing",
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]
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[[package]]
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name = "rustc_type_ir"
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version = "0.0.0"
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dependencies = [
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"bitflags",
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"rustc_data_structures",
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"rustc_index",
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"rustc_serialize",
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]
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[[package]]
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name = "rustc_typeck"
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version = "0.0.0"
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@ -30,3 +30,4 @@ chalk-ir = "0.36.0"
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smallvec = { version = "1.0", features = ["union", "may_dangle"] }
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measureme = "9.0.0"
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rustc_session = { path = "../rustc_session" }
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rustc_type_ir = { path = "../rustc_type_ir" }
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@ -56,7 +56,7 @@
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pub use self::sty::RegionKind;
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pub use self::sty::RegionKind::*;
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pub use self::sty::TyKind::*;
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pub use self::sty::{Binder, BoundTy, BoundTyKind, BoundVar, DebruijnIndex, INNERMOST};
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pub use self::sty::{Binder, BoundTy, BoundTyKind, BoundVar};
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pub use self::sty::{BoundRegion, EarlyBoundRegion, FreeRegion, Region};
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pub use self::sty::{CanonicalPolyFnSig, FnSig, GenSig, PolyFnSig, PolyGenSig};
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pub use self::sty::{ClosureSubsts, GeneratorSubsts, TypeAndMut, UpvarSubsts};
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@ -67,6 +67,7 @@
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pub use self::sty::{ExistentialTraitRef, PolyExistentialTraitRef};
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pub use self::sty::{PolyTraitRef, TraitRef, TyKind};
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pub use crate::ty::diagnostics::*;
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pub use rustc_type_ir::{DebruijnIndex, TypeFlags, INNERMOST};
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pub use self::binding::BindingMode;
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pub use self::binding::BindingMode::*;
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@ -497,91 +498,6 @@ pub struct CReaderCacheKey {
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pub pos: usize,
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}
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bitflags! {
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/// Flags that we track on types. These flags are propagated upwards
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/// through the type during type construction, so that we can quickly check
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/// whether the type has various kinds of types in it without recursing
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/// over the type itself.
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pub struct TypeFlags: u32 {
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// Does this have parameters? Used to determine whether substitution is
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// required.
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/// Does this have [Param]?
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const HAS_TY_PARAM = 1 << 0;
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/// Does this have [ReEarlyBound]?
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const HAS_RE_PARAM = 1 << 1;
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/// Does this have [ConstKind::Param]?
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const HAS_CT_PARAM = 1 << 2;
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const NEEDS_SUBST = TypeFlags::HAS_TY_PARAM.bits
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| TypeFlags::HAS_RE_PARAM.bits
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| TypeFlags::HAS_CT_PARAM.bits;
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/// Does this have [Infer]?
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const HAS_TY_INFER = 1 << 3;
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/// Does this have [ReVar]?
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const HAS_RE_INFER = 1 << 4;
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/// Does this have [ConstKind::Infer]?
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const HAS_CT_INFER = 1 << 5;
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/// Does this have inference variables? Used to determine whether
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/// inference is required.
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const NEEDS_INFER = TypeFlags::HAS_TY_INFER.bits
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| TypeFlags::HAS_RE_INFER.bits
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| TypeFlags::HAS_CT_INFER.bits;
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/// Does this have [Placeholder]?
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const HAS_TY_PLACEHOLDER = 1 << 6;
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/// Does this have [RePlaceholder]?
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const HAS_RE_PLACEHOLDER = 1 << 7;
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/// Does this have [ConstKind::Placeholder]?
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const HAS_CT_PLACEHOLDER = 1 << 8;
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/// `true` if there are "names" of regions and so forth
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/// that are local to a particular fn/inferctxt
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const HAS_FREE_LOCAL_REGIONS = 1 << 9;
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/// `true` if there are "names" of types and regions and so forth
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/// that are local to a particular fn
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const HAS_FREE_LOCAL_NAMES = TypeFlags::HAS_TY_PARAM.bits
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| TypeFlags::HAS_CT_PARAM.bits
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| TypeFlags::HAS_TY_INFER.bits
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| TypeFlags::HAS_CT_INFER.bits
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| TypeFlags::HAS_TY_PLACEHOLDER.bits
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| TypeFlags::HAS_CT_PLACEHOLDER.bits
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| TypeFlags::HAS_FREE_LOCAL_REGIONS.bits;
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/// Does this have [Projection]?
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const HAS_TY_PROJECTION = 1 << 10;
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/// Does this have [Opaque]?
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const HAS_TY_OPAQUE = 1 << 11;
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/// Does this have [ConstKind::Unevaluated]?
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const HAS_CT_PROJECTION = 1 << 12;
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/// Could this type be normalized further?
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const HAS_PROJECTION = TypeFlags::HAS_TY_PROJECTION.bits
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| TypeFlags::HAS_TY_OPAQUE.bits
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| TypeFlags::HAS_CT_PROJECTION.bits;
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/// Is an error type/const reachable?
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const HAS_ERROR = 1 << 13;
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/// Does this have any region that "appears free" in the type?
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/// Basically anything but [ReLateBound] and [ReErased].
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const HAS_FREE_REGIONS = 1 << 14;
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/// Does this have any [ReLateBound] regions? Used to check
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/// if a global bound is safe to evaluate.
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const HAS_RE_LATE_BOUND = 1 << 15;
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/// Does this have any [ReErased] regions?
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const HAS_RE_ERASED = 1 << 16;
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/// Does this value have parameters/placeholders/inference variables which could be
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/// replaced later, in a way that would change the results of `impl` specialization?
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const STILL_FURTHER_SPECIALIZABLE = 1 << 17;
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}
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}
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#[allow(rustc::usage_of_ty_tykind)]
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pub struct TyS<'tcx> {
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/// This field shouldn't be used directly and may be removed in the future.
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@ -1289,53 +1289,6 @@ pub fn to_const(self, tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> &'tcx ty::Const<'tcx>
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}
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}
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rustc_index::newtype_index! {
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/// A [De Bruijn index][dbi] is a standard means of representing
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/// regions (and perhaps later types) in a higher-ranked setting. In
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/// particular, imagine a type like this:
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///
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/// for<'a> fn(for<'b> fn(&'b isize, &'a isize), &'a char)
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/// ^ ^ | | |
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/// | | | | |
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/// | +------------+ 0 | |
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/// | | |
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/// +----------------------------------+ 1 |
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/// | |
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/// +----------------------------------------------+ 0
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///
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/// In this type, there are two binders (the outer fn and the inner
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/// fn). We need to be able to determine, for any given region, which
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/// fn type it is bound by, the inner or the outer one. There are
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/// various ways you can do this, but a De Bruijn index is one of the
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/// more convenient and has some nice properties. The basic idea is to
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/// count the number of binders, inside out. Some examples should help
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/// clarify what I mean.
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///
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/// Let's start with the reference type `&'b isize` that is the first
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/// argument to the inner function. This region `'b` is assigned a De
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/// Bruijn index of 0, meaning "the innermost binder" (in this case, a
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/// fn). The region `'a` that appears in the second argument type (`&'a
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/// isize`) would then be assigned a De Bruijn index of 1, meaning "the
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/// second-innermost binder". (These indices are written on the arrays
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/// in the diagram).
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///
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/// What is interesting is that De Bruijn index attached to a particular
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/// variable will vary depending on where it appears. For example,
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/// the final type `&'a char` also refers to the region `'a` declared on
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/// the outermost fn. But this time, this reference is not nested within
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/// any other binders (i.e., it is not an argument to the inner fn, but
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/// rather the outer one). Therefore, in this case, it is assigned a
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/// De Bruijn index of 0, because the innermost binder in that location
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/// is the outer fn.
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///
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/// [dbi]: https://en.wikipedia.org/wiki/De_Bruijn_index
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#[derive(HashStable)]
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pub struct DebruijnIndex {
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DEBUG_FORMAT = "DebruijnIndex({})",
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const INNERMOST = 0,
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}
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}
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pub type Region<'tcx> = &'tcx RegionKind;
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/// Representation of regions. Note that the NLL checker uses a distinct
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@ -1450,7 +1403,7 @@ pub enum RegionKind {
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/// Region bound in a function scope, which will be substituted when the
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/// function is called.
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ReLateBound(DebruijnIndex, BoundRegion),
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ReLateBound(ty::DebruijnIndex, BoundRegion),
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/// When checking a function body, the types of all arguments and so forth
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/// that refer to bound region parameters are modified to refer to free
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@ -1614,65 +1567,6 @@ pub fn item_def_id(&self) -> DefId {
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}
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}
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impl DebruijnIndex {
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/// Returns the resulting index when this value is moved into
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/// `amount` number of new binders. So, e.g., if you had
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///
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/// for<'a> fn(&'a x)
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///
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/// and you wanted to change it to
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///
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/// for<'a> fn(for<'b> fn(&'a x))
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///
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/// you would need to shift the index for `'a` into a new binder.
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#[must_use]
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pub fn shifted_in(self, amount: u32) -> DebruijnIndex {
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DebruijnIndex::from_u32(self.as_u32() + amount)
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}
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/// Update this index in place by shifting it "in" through
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/// `amount` number of binders.
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pub fn shift_in(&mut self, amount: u32) {
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*self = self.shifted_in(amount);
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}
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/// Returns the resulting index when this value is moved out from
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/// `amount` number of new binders.
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#[must_use]
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pub fn shifted_out(self, amount: u32) -> DebruijnIndex {
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DebruijnIndex::from_u32(self.as_u32() - amount)
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}
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/// Update in place by shifting out from `amount` binders.
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pub fn shift_out(&mut self, amount: u32) {
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*self = self.shifted_out(amount);
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}
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/// Adjusts any De Bruijn indices so as to make `to_binder` the
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/// innermost binder. That is, if we have something bound at `to_binder`,
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/// it will now be bound at INNERMOST. This is an appropriate thing to do
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/// when moving a region out from inside binders:
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///
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/// ```
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/// for<'a> fn(for<'b> for<'c> fn(&'a u32), _)
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/// // Binder: D3 D2 D1 ^^
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/// ```
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///
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/// Here, the region `'a` would have the De Bruijn index D3,
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/// because it is the bound 3 binders out. However, if we wanted
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/// to refer to that region `'a` in the second argument (the `_`),
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/// those two binders would not be in scope. In that case, we
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/// might invoke `shift_out_to_binder(D3)`. This would adjust the
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/// De Bruijn index of `'a` to D1 (the innermost binder).
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///
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/// If we invoke `shift_out_to_binder` and the region is in fact
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/// bound by one of the binders we are shifting out of, that is an
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/// error (and should fail an assertion failure).
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pub fn shifted_out_to_binder(self, to_binder: DebruijnIndex) -> Self {
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self.shifted_out(to_binder.as_u32() - INNERMOST.as_u32())
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}
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}
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/// Region utilities
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impl RegionKind {
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/// Is this region named by the user?
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@ -1703,7 +1597,7 @@ pub fn is_placeholder(&self) -> bool {
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}
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}
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pub fn bound_at_or_above_binder(&self, index: DebruijnIndex) -> bool {
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pub fn bound_at_or_above_binder(&self, index: ty::DebruijnIndex) -> bool {
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match *self {
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ty::ReLateBound(debruijn, _) => debruijn >= index,
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_ => false,
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14
compiler/rustc_type_ir/Cargo.toml
Normal file
14
compiler/rustc_type_ir/Cargo.toml
Normal file
@ -0,0 +1,14 @@
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[package]
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name = "rustc_type_ir"
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version = "0.0.0"
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authors = ["The Rust Project Developers"]
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edition = "2018"
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[lib]
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doctest = false
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[dependencies]
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bitflags = "1.2.1"
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rustc_index = { path = "../rustc_index" }
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rustc_serialize = { path = "../rustc_serialize" }
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rustc_data_structures = { path = "../rustc_data_structures" }
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204
compiler/rustc_type_ir/src/lib.rs
Normal file
204
compiler/rustc_type_ir/src/lib.rs
Normal file
@ -0,0 +1,204 @@
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#![feature(never_type)]
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#![feature(const_panic)]
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#![feature(control_flow_enum)]
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#[macro_use]
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extern crate bitflags;
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use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
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bitflags! {
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/// Flags that we track on types. These flags are propagated upwards
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/// through the type during type construction, so that we can quickly check
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/// whether the type has various kinds of types in it without recursing
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/// over the type itself.
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pub struct TypeFlags: u32 {
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// Does this have parameters? Used to determine whether substitution is
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// required.
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/// Does this have `Param`?
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const HAS_TY_PARAM = 1 << 0;
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/// Does this have `ReEarlyBound`?
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const HAS_RE_PARAM = 1 << 1;
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/// Does this have `ConstKind::Param`?
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const HAS_CT_PARAM = 1 << 2;
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const NEEDS_SUBST = TypeFlags::HAS_TY_PARAM.bits
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| TypeFlags::HAS_RE_PARAM.bits
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| TypeFlags::HAS_CT_PARAM.bits;
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/// Does this have `Infer`?
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const HAS_TY_INFER = 1 << 3;
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/// Does this have `ReVar`?
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const HAS_RE_INFER = 1 << 4;
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/// Does this have `ConstKind::Infer`?
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const HAS_CT_INFER = 1 << 5;
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/// Does this have inference variables? Used to determine whether
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/// inference is required.
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const NEEDS_INFER = TypeFlags::HAS_TY_INFER.bits
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| TypeFlags::HAS_RE_INFER.bits
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| TypeFlags::HAS_CT_INFER.bits;
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/// Does this have `Placeholder`?
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const HAS_TY_PLACEHOLDER = 1 << 6;
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/// Does this have `RePlaceholder`?
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const HAS_RE_PLACEHOLDER = 1 << 7;
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/// Does this have `ConstKind::Placeholder`?
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const HAS_CT_PLACEHOLDER = 1 << 8;
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/// `true` if there are "names" of regions and so forth
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/// that are local to a particular fn/inferctxt
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const HAS_FREE_LOCAL_REGIONS = 1 << 9;
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/// `true` if there are "names" of types and regions and so forth
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/// that are local to a particular fn
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const HAS_FREE_LOCAL_NAMES = TypeFlags::HAS_TY_PARAM.bits
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| TypeFlags::HAS_CT_PARAM.bits
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| TypeFlags::HAS_TY_INFER.bits
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| TypeFlags::HAS_CT_INFER.bits
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| TypeFlags::HAS_TY_PLACEHOLDER.bits
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| TypeFlags::HAS_CT_PLACEHOLDER.bits
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| TypeFlags::HAS_FREE_LOCAL_REGIONS.bits;
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/// Does this have `Projection`?
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const HAS_TY_PROJECTION = 1 << 10;
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/// Does this have `Opaque`?
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const HAS_TY_OPAQUE = 1 << 11;
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/// Does this have `ConstKind::Unevaluated`?
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const HAS_CT_PROJECTION = 1 << 12;
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/// Could this type be normalized further?
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const HAS_PROJECTION = TypeFlags::HAS_TY_PROJECTION.bits
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| TypeFlags::HAS_TY_OPAQUE.bits
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| TypeFlags::HAS_CT_PROJECTION.bits;
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/// Is an error type/const reachable?
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const HAS_ERROR = 1 << 13;
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/// Does this have any region that "appears free" in the type?
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/// Basically anything but `ReLateBound` and `ReErased`.
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const HAS_FREE_REGIONS = 1 << 14;
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/// Does this have any `ReLateBound` regions? Used to check
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/// if a global bound is safe to evaluate.
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const HAS_RE_LATE_BOUND = 1 << 15;
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/// Does this have any `ReErased` regions?
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const HAS_RE_ERASED = 1 << 16;
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/// Does this value have parameters/placeholders/inference variables which could be
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/// replaced later, in a way that would change the results of `impl` specialization?
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const STILL_FURTHER_SPECIALIZABLE = 1 << 17;
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}
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}
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rustc_index::newtype_index! {
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/// A [De Bruijn index][dbi] is a standard means of representing
|
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/// regions (and perhaps later types) in a higher-ranked setting. In
|
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/// particular, imagine a type like this:
|
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///
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/// for<'a> fn(for<'b> fn(&'b isize, &'a isize), &'a char)
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/// ^ ^ | | |
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/// | | | | |
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/// | +------------+ 0 | |
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/// | | |
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/// +----------------------------------+ 1 |
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/// | |
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/// +----------------------------------------------+ 0
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///
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/// In this type, there are two binders (the outer fn and the inner
|
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/// fn). We need to be able to determine, for any given region, which
|
||||
/// fn type it is bound by, the inner or the outer one. There are
|
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/// various ways you can do this, but a De Bruijn index is one of the
|
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/// more convenient and has some nice properties. The basic idea is to
|
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/// count the number of binders, inside out. Some examples should help
|
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/// clarify what I mean.
|
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///
|
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/// Let's start with the reference type `&'b isize` that is the first
|
||||
/// argument to the inner function. This region `'b` is assigned a De
|
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/// Bruijn index of 0, meaning "the innermost binder" (in this case, a
|
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/// fn). The region `'a` that appears in the second argument type (`&'a
|
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/// isize`) would then be assigned a De Bruijn index of 1, meaning "the
|
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/// second-innermost binder". (These indices are written on the arrays
|
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/// in the diagram).
|
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///
|
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/// What is interesting is that De Bruijn index attached to a particular
|
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/// variable will vary depending on where it appears. For example,
|
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/// the final type `&'a char` also refers to the region `'a` declared on
|
||||
/// the outermost fn. But this time, this reference is not nested within
|
||||
/// any other binders (i.e., it is not an argument to the inner fn, but
|
||||
/// rather the outer one). Therefore, in this case, it is assigned a
|
||||
/// De Bruijn index of 0, because the innermost binder in that location
|
||||
/// is the outer fn.
|
||||
///
|
||||
/// [dbi]: https://en.wikipedia.org/wiki/De_Bruijn_index
|
||||
pub struct DebruijnIndex {
|
||||
DEBUG_FORMAT = "DebruijnIndex({})",
|
||||
const INNERMOST = 0,
|
||||
}
|
||||
}
|
||||
|
||||
impl DebruijnIndex {
|
||||
/// Returns the resulting index when this value is moved into
|
||||
/// `amount` number of new binders. So, e.g., if you had
|
||||
///
|
||||
/// for<'a> fn(&'a x)
|
||||
///
|
||||
/// and you wanted to change it to
|
||||
///
|
||||
/// for<'a> fn(for<'b> fn(&'a x))
|
||||
///
|
||||
/// you would need to shift the index for `'a` into a new binder.
|
||||
#[must_use]
|
||||
pub fn shifted_in(self, amount: u32) -> DebruijnIndex {
|
||||
DebruijnIndex::from_u32(self.as_u32() + amount)
|
||||
}
|
||||
|
||||
/// Update this index in place by shifting it "in" through
|
||||
/// `amount` number of binders.
|
||||
pub fn shift_in(&mut self, amount: u32) {
|
||||
*self = self.shifted_in(amount);
|
||||
}
|
||||
|
||||
/// Returns the resulting index when this value is moved out from
|
||||
/// `amount` number of new binders.
|
||||
#[must_use]
|
||||
pub fn shifted_out(self, amount: u32) -> DebruijnIndex {
|
||||
DebruijnIndex::from_u32(self.as_u32() - amount)
|
||||
}
|
||||
|
||||
/// Update in place by shifting out from `amount` binders.
|
||||
pub fn shift_out(&mut self, amount: u32) {
|
||||
*self = self.shifted_out(amount);
|
||||
}
|
||||
|
||||
/// Adjusts any De Bruijn indices so as to make `to_binder` the
|
||||
/// innermost binder. That is, if we have something bound at `to_binder`,
|
||||
/// it will now be bound at INNERMOST. This is an appropriate thing to do
|
||||
/// when moving a region out from inside binders:
|
||||
///
|
||||
/// ```
|
||||
/// for<'a> fn(for<'b> for<'c> fn(&'a u32), _)
|
||||
/// // Binder: D3 D2 D1 ^^
|
||||
/// ```
|
||||
///
|
||||
/// Here, the region `'a` would have the De Bruijn index D3,
|
||||
/// because it is the bound 3 binders out. However, if we wanted
|
||||
/// to refer to that region `'a` in the second argument (the `_`),
|
||||
/// those two binders would not be in scope. In that case, we
|
||||
/// might invoke `shift_out_to_binder(D3)`. This would adjust the
|
||||
/// De Bruijn index of `'a` to D1 (the innermost binder).
|
||||
///
|
||||
/// If we invoke `shift_out_to_binder` and the region is in fact
|
||||
/// bound by one of the binders we are shifting out of, that is an
|
||||
/// error (and should fail an assertion failure).
|
||||
pub fn shifted_out_to_binder(self, to_binder: DebruijnIndex) -> Self {
|
||||
self.shifted_out(to_binder.as_u32() - INNERMOST.as_u32())
|
||||
}
|
||||
}
|
||||
|
||||
impl<CTX> HashStable<CTX> for DebruijnIndex {
|
||||
fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
|
||||
self.as_u32().hash_stable(ctx, hasher);
|
||||
}
|
||||
}
|
Loading…
Reference in New Issue
Block a user