Fix doc links
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3 changed files with 22 additions and 22 deletions
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@ -1,18 +1,18 @@
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//! As explained in [`super::usefulness`], values and patterns are made from constructors applied to
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//! As explained in [`crate::usefulness`], values and patterns are made from constructors applied to
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//! fields. This file defines a `Constructor` enum and various operations to manipulate them.
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//!
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//! There are two important bits of core logic in this file: constructor inclusion and constructor
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//! splitting. Constructor inclusion, i.e. whether a constructor is included in/covered by another,
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//! is straightforward and defined in [`Constructor::is_covered_by`].
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//!
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//! Constructor splitting is mentioned in [`super::usefulness`] but not detailed. We describe it
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//! Constructor splitting is mentioned in [`crate::usefulness`] but not detailed. We describe it
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//! precisely here.
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//!
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//!
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//!
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//! # Constructor grouping and splitting
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//!
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//! As explained in the corresponding section in [`super::usefulness`], to make usefulness tractable
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//! As explained in the corresponding section in [`crate::usefulness`], to make usefulness tractable
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//! we need to group together constructors that have the same effect when they are used to
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//! specialize the matrix.
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//!
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@ -28,7 +28,7 @@
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//! In this example we can restrict specialization to 5 cases: `0..50`, `50..=100`, `101..=150`,
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//! `151..=200` and `200..`.
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//!
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//! In [`super::usefulness`], we had said that `specialize` only takes value-only constructors. We
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//! In [`crate::usefulness`], we had said that `specialize` only takes value-only constructors. We
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//! now relax this restriction: we allow `specialize` to take constructors like `0..50` as long as
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//! we're careful to only do that with constructors that make sense. For example, `specialize(0..50,
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//! (0..=100, true))` is sensible, but `specialize(50..=200, (0..=100, true))` is not.
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@ -40,9 +40,9 @@
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//! - That have no non-trivial intersection with any of the constructors in the column (i.e. they're
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//! each either disjoint with or covered by any given column constructor).
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//!
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//! We compute this in two steps: first [`ConstructorSet::for_ty`] determines the set of all
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//! possible constructors for the type. Then [`ConstructorSet::split`] looks at the column of
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//! constructors and splits the set into groups accordingly. The precise invariants of
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//! We compute this in two steps: first [`crate::cx::MatchCheckCtxt::ctors_for_ty`] determines the
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//! set of all possible constructors for the type. Then [`ConstructorSet::split`] looks at the
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//! column of constructors and splits the set into groups accordingly. The precise invariants of
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//! [`ConstructorSet::split`] is described in [`SplitConstructorSet`].
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//!
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//! Constructor splitting has two interesting special cases: integer range splitting (see
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@ -71,10 +71,10 @@
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//! `Wildcard`.
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//!
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//! The only place where we care about which constructors `Missing` represents is in diagnostics
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//! (see `super::usefulness::WitnessMatrix::apply_constructor`).
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//! (see `crate::usefulness::WitnessMatrix::apply_constructor`).
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//!
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//! We choose whether to specialize with `Missing` in
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//! `super::usefulness::compute_exhaustiveness_and_reachability`.
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//! `crate::usefulness::compute_exhaustiveness_and_usefulness`.
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//!
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//!
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//!
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@ -88,7 +88,7 @@
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//! `exhaustive_patterns` feature is turned on, in which case we do treat them as empty. And also
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//! except if the type has no constructors (like `enum Void {}` but not like `Result<!, !>`), we
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//! specifically allow `match void {}` to be exhaustive. There are additionally considerations of
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//! place validity that are handled in `super::usefulness`. Yes this is a bit tricky.
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//! place validity that are handled in `crate::usefulness`. Yes this is a bit tricky.
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//!
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//! The second thing is that regardless of the above, it is always allowed to use all the
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//! constructors of a type. For example, all the following is ok:
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@ -136,8 +136,8 @@
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//! the algorithm can't distinguish them from a nonempty constructor. The only known case where this
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//! could happen is the `[..]` pattern on `[!; N]` with `N > 0` so we must take care to not emit it.
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//!
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//! This is all handled by [`ConstructorSet::for_ty`] and [`ConstructorSet::split`]. The invariants
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//! of [`SplitConstructorSet`] are also of interest.
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//! This is all handled by [`crate::cx::MatchCheckCtxt::ctors_for_ty`] and
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//! [`ConstructorSet::split`]. The invariants of [`SplitConstructorSet`] are also of interest.
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//!
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//!
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//!
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@ -18,11 +18,10 @@ use crate::MatchArm;
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/// A column of patterns in the matrix, where a column is the intuitive notion of "subpatterns that
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/// inspect the same subvalue/place".
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/// This is used to traverse patterns column-by-column for lints. Despite similarities with
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/// [`compute_exhaustiveness_and_usefulness`], this does a different traversal. Notably this is
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/// linear in the depth of patterns, whereas `compute_exhaustiveness_and_usefulness` is worst-case
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/// exponential (exhaustiveness is NP-complete). The core difference is that we treat sub-columns
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/// separately.
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/// This is used to traverse patterns column-by-column for lints. Despite similarities with the
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/// algorithm in [`crate::usefulness`], this does a different traversal. Notably this is linear in
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/// the depth of patterns, whereas `compute_exhaustiveness_and_usefulness` is worst-case exponential
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/// (exhaustiveness is NP-complete). The core difference is that we treat sub-columns separately.
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///
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/// This must not contain an or-pattern. `specialize` takes care to expand them.
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///
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@ -97,8 +97,9 @@
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//! - `matches!([v0], [p0, .., p1]) := false` (incompatible lengths)
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//! - `matches!([v0, v1, v2], [p0, .., p1]) := matches!(v0, p0) && matches!(v2, p1)`
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//!
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//! Constructors, fields and relevant operations are defined in the [`super::deconstruct_pat`]
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//! module. The question of whether a constructor is matched by another one is answered by
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//! Constructors and relevant operations are defined in the [`crate::constructor`] module. A
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//! representation of patterns that uses constructors is available in [`crate::pat`]. The question
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//! of whether a constructor is matched by another one is answered by
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//! [`Constructor::is_covered_by`].
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//!
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//! Note 1: variable bindings (like the `x` in `Some(x)`) match anything, so we treat them as wildcards.
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@ -241,8 +242,8 @@
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//! Therefore `usefulness(tp_1, tp_2, tq)` returns the single witness-tuple `[Variant2(Some(true), 0)]`.
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//!
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//!
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//! Computing the set of constructors for a type is done in [`ConstructorSet::for_ty`]. See the
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//! following sections for more accurate versions of the algorithm and corresponding links.
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//! Computing the set of constructors for a type is done in [`MatchCheckCtxt::ctors_for_ty`]. See
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//! the following sections for more accurate versions of the algorithm and corresponding links.
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//!
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//!
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//!
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@ -295,7 +296,7 @@
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//! the same reasoning, we only need to try two cases: `North`, and "everything else".
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//!
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//! We call _constructor splitting_ the operation that computes such a minimal set of cases to try.
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//! This is done in [`ConstructorSet::split`] and explained in [`super::deconstruct_pat`].
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//! This is done in [`ConstructorSet::split`] and explained in [`crate::constructor`].
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//!
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//!
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//!
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