Agda-2.6.20240714: A dependently typed functional programming language and proof assistant
Safe HaskellNone
LanguageHaskell2010

Agda.TypeChecking.Conversion

Synopsis

Documentation

type MonadConversion (m :: Type -> Type) = (PureTCM m, MonadConstraint m, MonadMetaSolver m, MonadError TCErr m, MonadWarning m, MonadStatistics m, MonadFresh ProblemId m, MonadFresh Int m, MonadFail m) Source #

tryConversion :: (MonadConstraint m, MonadWarning m, MonadError TCErr m, MonadFresh ProblemId m) => m () -> m Bool Source #

Try whether a computation runs without errors or new constraints (may create new metas, though). Restores state upon failure.

tryConversion' :: (MonadConstraint m, MonadWarning m, MonadError TCErr m, MonadFresh ProblemId m) => m a -> m (Maybe a) Source #

Try whether a computation runs without errors or new constraints (may create new metas, though). Return Just the result upon success. Return Nothing and restore state upon failure.

sameVars :: Elims -> Elims -> Bool Source #

Check if to lists of arguments are the same (and all variables). Precondition: the lists have the same length.

intersectVars :: Elims -> Elims -> Maybe [Bool] Source #

intersectVars us vs checks whether all relevant elements in us and vs are variables, and if yes, returns a prune list which says True for arguments which are different and can be pruned.

guardPointerEquality :: MonadConversion m => a -> a -> String -> m () -> m () Source #

guardPointerEquality x y s m behaves as m if x and y are equal as pointers, or does nothing otherwise. Use with care, see the documentation for unsafeComparePointers

convError :: TypeError -> TCM () Source #

Ignore errors in irrelevant context.

compareTerm :: MonadConversion m => Comparison -> Type -> Term -> Term -> m () Source #

Type directed equality on values.

compareAs :: MonadConversion m => Comparison -> CompareAs -> Term -> Term -> m () Source #

Type directed equality on terms or types.

assignE :: MonadConversion m => CompareDirection -> MetaId -> Elims -> Term -> CompareAs -> (Term -> Term -> m ()) -> m () Source #

Try to assign meta. If meta is projected, try to eta-expand and run conversion check again.

computeElimHeadType :: MonadConversion m => QName -> Elims -> Elims -> m Type Source #

Compute the head type of an elimination. For projection-like functions this requires inferring the type of the principal argument.

compareAtom :: MonadConversion m => Comparison -> CompareAs -> Term -> Term -> m () Source #

Syntax directed equality on atomic values

compareMetas :: MonadConversion m => Comparison -> CompareAs -> MetaId -> Elims -> MetaId -> Elims -> m () Source #

Check whether x xArgs cmp y yArgs

compareDom Source #

Arguments

:: (MonadConversion m, Free c) 
=> Comparison

cmp The comparison direction

-> Dom Type

a1 The smaller domain.

-> Dom Type

a2 The other domain.

-> Abs b

b1 The smaller codomain.

-> Abs c

b2 The bigger codomain.

-> m ()

Continuation if mismatch in Hiding.

-> m ()

Continuation if mismatch in Relevance.

-> m ()

Continuation if mismatch in Quantity.

-> m ()

Continuation if mismatch in Cohesion.

-> m ()

Continuation if mismatch in annFinite.

-> m ()

Continuation if comparison is successful.

-> m () 

Check whether a1 cmp a2 and continue in context extended by a1.

antiUnify :: MonadConversion m => ProblemId -> Type -> Term -> Term -> m Term Source #

When comparing argument spines (in compareElims) where the first arguments don't match, we keep going, substituting the anti-unification of the two terms in the telescope. More precisely:

@ (u = v : A)[pid] w = antiUnify pid A u v us = vs : Δ[w/x] ------------------------------------------------------------- u us = v vs : (x : A) Δ @

The simplest case of anti-unification is to return a fresh metavariable (created by blockTermOnProblem), but if there's shared structure between the two terms we can expose that.

This is really a crutch that lets us get away with things that otherwise would require heterogenous conversion checking. See for instance issue #2384.

compareElims :: MonadConversion m => [Polarity] -> [IsForced] -> Type -> Term -> [Elim] -> [Elim] -> m () Source #

compareElims pols a v els1 els2 performs type-directed equality on eliminator spines. t is the type of the head v.

compareIrrelevant :: MonadConversion m => Type -> Term -> Term -> m () Source #

Compare two terms in irrelevant position. This always succeeds. However, we can dig for solutions of irrelevant metas in the terms we compare. (Certainly not the systematic solution, that'd be proof search...)

compareWithPol :: MonadConversion m => Polarity -> (Comparison -> a -> a -> m ()) -> a -> a -> m () Source #

compareArgs :: MonadConversion m => [Polarity] -> [IsForced] -> Type -> Term -> Args -> Args -> m () Source #

Type-directed equality on argument lists

Types

compareType :: MonadConversion m => Comparison -> Type -> Type -> m () Source #

Equality on Types

coerce :: (MonadConversion m, MonadTCM m) => Comparison -> Term -> Type -> Type -> m Term Source #

coerce v a b coerces v : a to type b, returning a v' : b with maybe extra hidden applications or hidden abstractions.

In principle, this function can host coercive subtyping, but currently it only tries to fix problems with hidden function types.

coerceSize :: MonadConversion m => (Type -> Type -> m ()) -> Term -> Type -> Type -> m () Source #

Account for situations like k : (Size< j) <= (Size< k + 1)

Actually, the semantics is (Size<= k) ∩ (Size< j) ⊆ rhs which gives a disjunctive constraint. Mmmh, looks like stuff TODO.

For now, we do a cheap heuristics.

Sorts and levels

leqSort :: MonadConversion m => Sort -> Sort -> m () Source #

Check that the first sort is less or equal to the second.

We can put SizeUniv below Inf, but otherwise, it is unrelated to the other universes.

equalSort :: MonadConversion m => Sort -> Sort -> m () Source #

Check that the first sort equal to the second.

forallFaceMaps :: MonadConversion m => Term -> (IntMap Bool -> Blocker -> Term -> m a) -> (IntMap Bool -> Substitution -> m a) -> m [a] Source #

type Conj = (IntMap BoolSet, [Term]) Source #

isCanonical :: [Conj] -> Bool Source #

leqInterval :: MonadConversion m => [Conj] -> [Conj] -> m Bool Source #

leqInterval r q = r ≤ q in the I lattice. (∨ r_i) ≤ (∨ q_j) iff ∀ i. ∃ j. r_i ≤ q_j

leqConj :: MonadConversion m => Conj -> Conj -> m Bool Source #

leqConj r q = r ≤ q in the I lattice, when r and q are conjuctions. ' (∧ r_i) ≤ (∧ q_j) iff ' (∧ r_i) ∧ (∧ q_j) = (∧ r_i) iff ' {r_i | i} ∪ {q_j | j} = {r_i | i} iff ' {q_j | j} ⊆ {r_i | i}

equalTermOnFace :: MonadConversion m => Term -> Type -> Term -> Term -> m () Source #

equalTermOnFace φ A u v = _ , φ ⊢ u = v : A

Definitions