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Refactor pattern-matching usefulness algorithm#65160

Closed

Nadrieril wants to merge 87 commits into

rust-lang:masterrust-lang/rust:masterfrom

Nadrieril:refactor-usefulnessNadrieril/rust:refactor-usefulnessCopy head branch name to clipboard

Conversation Commits87 (87)Checks Files changed

Closed

Refactor pattern-matching usefulness algorithm#65160
Nadrieril wants to merge 87 commits into
rust-lang:masterfrom
Nadrieril:refactor-usefulness

Commits

Commits on Oct 18, 2019

Run `rustfmt`
Nadrieril
committed
Remove mention of old slice pattern syntax
Nadrieril
committed
Clarify and fix the explanation of the algorithm
Nadrieril
committed
Abstract out pattern stacks to make the code more legible
Nadrieril
committed
Remove some redundancy
Nadrieril
committed
Remove duplicate logic in compute_missing_constructors
Nadrieril
committed
Extract constructor application as a Constructor method
Nadrieril
committed
Refactor "wild constructor" construction
Nadrieril
committed
Clarify some variable names
Nadrieril
committed
`specialize` conceptually operates on a single pattern
Nadrieril
committed
Wording
Nadrieril
committed
Add some slice-pattern exhaustiveness tests
Nadrieril
committed
Rename Constructor::Slice to FixedLenSlice
Nadrieril
committed
IntRange::from_pat is redundant with pat_constructors
Nadrieril
committed
split_grouped_constructors only needs access to the list of used constructors
Nadrieril
committed
Share computation of used_ctors
Nadrieril
committed
Rework the exhaustiveness algorithm to better integrate meta-constructors
Nadrieril
committed
Define a MissingConstructors struct for cleanliness
Nadrieril
committed
Move is_non_exhaustive into MissingConstructors
Nadrieril
committed
Allow Constructor::apply to return more than one pattern
Nadrieril
committed
Define MissingConstructors meta-constructor and use it for witness reconstruction
Nadrieril
committed
Match constructor first instead of type first in various functions
Nadrieril
committed
Move constructor_sub_pattern_tys into wildcard_subpatterns
Nadrieril
committed
Replace wildcard-specific code paths with generalized specialization
Nadrieril
committed
Factor out some bits
Nadrieril
committed
Extract constructor splitting as a Constructor method
Nadrieril
committed
Rename pop_constructor back to specialize
Nadrieril
committed
Add Wildcard meta-constructor
Nadrieril
committed
pat_constructors now returns Wildcard when relevant
Nadrieril
committed
Avoid allocating in the common case of a single pattern
Nadrieril
committed
Invert condition for clarity
Nadrieril
committed
Clarify handling of uninhabited types
Nadrieril
committed
Gather together usefulness tests
Nadrieril
committed
MatchCheckCtxt::byte_array_map is unused since 7df1d9f6564cafca3758e5d629920c02df526989
Nadrieril
committed
No need to mutate MatchCheckCtxt anymore
Nadrieril
committed
Add comment about non_exhaustive feature
Nadrieril
committed
Use Wildcard instead of MissingConstructors when relevant
Nadrieril
committed
Make IntRange::subtract_from work on a single constructor
Nadrieril
committed
Factor out constructor subtraction
Nadrieril
committed
subtract_meta_constructor: match on constructor first
Nadrieril
committed
Extract constructor_intersects_pattern function
Nadrieril
committed
Inline constructor_covered_by_range and IntRange::from_pat
Nadrieril
committed
Use question mark instead of custom macro
Nadrieril
committed
Regroup similar code paths
Nadrieril
committed
Add a few more slice pattern usefulness tests
Nadrieril
committed
Add variable-length slice metaconstructor
Nadrieril
committed
Don't use max_slice_length when subtracting from VarLenSlice
Nadrieril
committed
Faster code path for subtracting from FixedLenSlice
Nadrieril
committed
Faster code path for subtracting from VarLenSlice
Nadrieril
committed
Make exhaustiveness error message more consistent for slice patterns
Nadrieril
committed
Prepare return types for or-patterns
Nadrieril
committed
MissingConstructors should not be compared for equality, but we need the impl
Nadrieril
committed
Add example run of the algorithm
Nadrieril
committed
Tidy up
Nadrieril
committed
Store both prefix and suffix length in VarLenSlice
Nadrieril
committed
max_slice_length only needs to look at constructors
Nadrieril
committed
Inline max_slice_length
Nadrieril
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Add some test cases
Nadrieril
committed
Splitting variable-length slices now respects the required invariant
Nadrieril
committed
PatCtxt is not useful anymore
Nadrieril
committed
Cleanup comments
Nadrieril
committed
Store Const in ConstantRange
Nadrieril
committed
Cleanup constructor_intersects_pattern
Nadrieril
committed
Implement nnethercote's suggestion
Nadrieril
committed
Implement Centril's suggestion
Nadrieril
committed
Incorporate varkor's review
Nadrieril
committed
Be more consistent in terminology
Nadrieril
committed
Move range exhaustiveness check to IntRange::intersection
Nadrieril
committed
Introduce IntRange meta-constructor
Nadrieril
committed
We no longer construct any ConstantValue or ConstantRange for non-integral types
Nadrieril
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Remove some unnecessary conversions between Constructor and IntRange
Nadrieril
committed
Ungate improved slice patterns diagnostics
Nadrieril
committed
Simplify slice subtraction as suggested by arielb1
Nadrieril
committed
Rewrite constructor_intersects_pattern as a match
Nadrieril
committed
Remove unnecessary Const conversion
Nadrieril
committed
Clarify why the naive algorithm may not terminate
Nadrieril
committed
Remove unneeded lifetime extensions
Nadrieril
committed
Use special `Captures` trait to solve issues with impl Iterator
Nadrieril
committed
`pat_constructors` doesn't need a `ty` parameter
Nadrieril
committed
Extract head constructors construction
Nadrieril
committed
Name the field of PatStack
Nadrieril
committed
Cache `pat_constructors` invocations
Nadrieril
committed
Compute constructors on PatStack construction
Nadrieril
committed
Restore performance
Nadrieril
committed
Don't rebuild the same matrix twice
Nadrieril
committed
Don't use SmallVec when we could use Option
Nadrieril
committed
Integrate comment fixes suggested by arielb1
Nadrieril
committed

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