diff options
Diffstat (limited to 'src/Soat/SecondOrder/Algebra.idr')
-rw-r--r-- | src/Soat/SecondOrder/Algebra.idr | 99 |
1 files changed, 56 insertions, 43 deletions
diff --git a/src/Soat/SecondOrder/Algebra.idr b/src/Soat/SecondOrder/Algebra.idr index c506c85..5dd53c5 100644 --- a/src/Soat/SecondOrder/Algebra.idr +++ b/src/Soat/SecondOrder/Algebra.idr @@ -1,6 +1,5 @@ module Soat.SecondOrder.Algebra -import Data.Morphism.Indexed import Data.Setoid.Indexed import Data.List.Elem @@ -13,11 +12,17 @@ extend : (U : a -> List a -> Type) -> (ctx : List a) -> Pair (List a) a -> Type extend x ctx ty = x (snd ty) (fst ty ++ ctx) public export -extendRel : {U : a -> List a -> Type} -> (rel : IRel (uncurry U)) - -> (ctx : List a) -> IRel (extend U ctx) +extendRel : {0 U : a -> List a -> Type} -> (rel : (ty : _) -> Rel (uncurry U ty)) + -> (ctx : List a) -> (ty : _) -> Rel (extend U ctx ty) extendRel rel ctx ty = rel (snd ty, fst ty ++ ctx) public export +extendFunc : {0 U, V : a -> List a -> Type} + -> (f : (t : a) -> (ctx : List a) -> U t ctx -> V t ctx) + -> (ctx : List a) -> (ty : Pair (List a) a) -> extend U ctx ty -> extend V ctx ty +extendFunc f ctx ty = f (snd ty) (fst ty ++ ctx) + +public export algebraOver : (sig : Signature) -> (U : sig.T -> List sig.T -> Type) -> Type algebraOver sig x = (ctx : List sig.T) -> {t : sig.T} -> (op : Op sig t) -> extend x ctx ^ op.arity -> x t ctx @@ -30,100 +35,108 @@ record RawAlgebra (0 sig : Signature) where sem : sig `algebraOver` U var : forall t, ctx . (i : Elem t ctx) -> U t ctx subst : (t : sig.T) -> (ctx : List sig.T) - -> forall ctx' . U t ctx' -> (\t => U t ctx) ^ ctx' -> U t ctx + -> forall ctx' . (tm : U t ctx') -> (tms : (\t => U t ctx) ^ ctx') -> U t ctx + +public export +(.extendSubst) : (a : RawAlgebra sig) -> (ctx : _) -> {ctx' : _} + -> (tms : (\t => a.U t ctx) ^ ctx') -> (ty : _) -> extend a.U ctx' ty -> extend a.U ctx ty +a .extendSubst ctx tms ty tm = a.subst + (snd ty) + (fst ty ++ ctx) + tm + (tabulate {is = fst ty} (a.var . elemJoinL {ys = ctx}) ++ + map (\t => a.rename t ([] {ys = fst ty} ++ reflexive {x = ctx})) tms) public export -record IsAlgebra (0 sig : Signature) (0 a : RawAlgebra sig) (0 rel : IRel (uncurry a.U)) where +record IsAlgebra (0 sig : Signature) (0 a : RawAlgebra sig) where constructor MkIsAlgebra - equivalence : IEquivalence (uncurry a.U) rel + equivalence : IndexedEquivalence (Pair sig.T (List sig.T)) (uncurry a.U) -- Congruences renameCong : (t : sig.T) -> {ctx, ctx' : _} -> (f : ctx `Sublist` ctx') - -> {tm, tm' : a.U t ctx} -> rel (t, ctx) tm tm' - -> rel (t, ctx') (a.rename t f tm) (a.rename t f tm') + -> {tm, tm' : a.U t ctx} -> equivalence.relation (t, ctx) tm tm' + -> equivalence.relation (t, ctx') (a.rename t f tm) (a.rename t f tm') semCong : (ctx : List sig.T) -> {t : sig.T} -> (op : Op sig t) -> {tms, tms' : extend a.U ctx ^ op.arity} - -> Pointwise (extendRel {U = a.U} rel ctx) tms tms' - -> rel (t, ctx) (a.sem ctx op tms) (a.sem ctx op tms') + -> Pointwise (extendRel {U = a.U} equivalence.relation ctx) tms tms' + -> equivalence.relation (t, ctx) (a.sem ctx op tms) (a.sem ctx op tms') substCong : (t : sig.T) -> (ctx : List sig.T) - -> {ctx' : _} -> {tm, tm' : a.U t ctx'} -> rel (t, ctx') tm tm' - -> {tms, tms' : (\t => a.U t ctx) ^ ctx'} -> Pointwise (\t => rel (t, ctx)) tms tms' - -> rel (t, ctx) (a.subst t ctx tm tms) (a.subst t ctx tm' tms') + -> {ctx' : _} -> {tm, tm' : a.U t ctx'} -> equivalence.relation (t, ctx') tm tm' + -> {tms, tms' : (\t => a.U t ctx) ^ ctx'} + -> Pointwise (\t => equivalence.relation (t, ctx)) tms tms' + -> equivalence.relation (t, ctx) (a.subst t ctx tm tms) (a.subst t ctx tm' tms') -- rename is functorial renameId : (t : sig.T) -> (ctx : List sig.T) -> (tm : a.U t ctx) - -> rel (t, ctx) (a.rename t {ctx = ctx} Relation.reflexive tm) tm + -> equivalence.relation (t, ctx) (a.rename t {ctx = ctx} Relation.reflexive tm) tm renameComp : (t : sig.T) -> {ctx, ctx', ctx'' : _} -> (f : ctx' `Sublist` ctx'') -> (g : ctx `Sublist` ctx') -> (tm : a.U t ctx) - -> rel (t, ctx'') (a.rename t (transitive g f) tm) (a.rename t f $ a.rename t g tm) + -> equivalence.relation (t, ctx'') + (a.rename t (transitive g f) tm) + (a.rename t f $ a.rename t g tm) -- sem are natural transformation semNat : {ctx, ctx' : _} -> (f : ctx `Sublist` ctx') -> {t : sig.T} -> (op : Op sig t) -> (tms : extend a.U ctx ^ op.arity) - -> rel (t, ctx') + -> equivalence.relation (t, ctx') (a.rename t f $ a.sem ctx op tms) (a.sem ctx' op $ map (\ty => a.rename (snd ty) (Relation.reflexive {x = fst ty} ++ f)) $ tms) -- var is natural transformation varNat : {t : _} -> {ctx, ctx' : _} -> (f : ctx `Sublist` ctx') -> (i : Elem t ctx) - -> rel (t, ctx') (a.rename t f $ a.var i) (a.var $ curry f i) + -> equivalence.relation (t, ctx') (a.rename t f $ a.var i) (a.var $ curry f i) -- subst is natural transformation substNat : (t : sig.T) -> {ctx, ctx' : _} -> (f : ctx `Sublist` ctx') -> {ctx'' : _} -> (tm : a.U t ctx'') -> (tms : (\t => a.U t ctx) ^ ctx'') - -> rel (t, ctx') + -> equivalence.relation (t, ctx') (a.rename t f $ a.subst t ctx tm tms) (a.subst t ctx' tm $ map (\t => a.rename t f) tms) -- subst is extranatural transformation substExnat : (t : sig.T) -> (ctx : List sig.T) -> {ctx', ctx'' : _} -> (f : ctx' `Sublist` ctx'') -> (tm : a.U t ctx') -> (tms : (\t => a.U t ctx) ^ ctx'') - -> rel (t, ctx) (a.subst t ctx (a.rename t f tm) tms) (a.subst t ctx tm (shuffle f tms)) + -> equivalence.relation (t, ctx) + (a.subst t ctx (a.rename t f tm) tms) + (a.subst t ctx tm (shuffle f tms)) -- var, subst is a monoid substComm : (t : sig.T) -> (ctx : List sig.T) -> {ctx', ctx'' : _} -> (tm : a.U t ctx'') -> (tms : (\t => a.U t ctx') ^ ctx'') -> (tms' : (\t => a.U t ctx) ^ ctx') - -> rel (t, ctx) + -> equivalence.relation (t, ctx) (a.subst t ctx (a.subst t ctx' tm tms) tms') (a.subst t ctx tm $ map (\t, tm => a.subst t ctx tm tms') tms) substVarL : {t : _} -> (ctx : List sig.T) -> {ctx' : _} -> (i : Elem t ctx') -> (tms : (\t => a.U t ctx) ^ ctx') - -> rel (t, ctx) (a.subst t ctx (a.var i) tms) (index tms i) + -> equivalence.relation (t, ctx) (a.subst t ctx (a.var i) tms) (index tms i) substVarR : (t : sig.T) -> (ctx : List sig.T) -> (tm : a.U t ctx) - -> rel (t, ctx) (a.subst t ctx {ctx' = ctx} tm $ tabulate a.var) tm + -> equivalence.relation (t, ctx) (a.subst t ctx {ctx' = ctx} tm $ tabulate a.var) tm -- sem, var and subst are compatible substCompat : (ctx : List sig.T) -> {t : sig.T} -> (op : Op sig t) -> {ctx' : _} -> (tms : extend a.U ctx' ^ op.arity) -> (tms' : (\t => a.U t ctx) ^ ctx') - -> rel (t, ctx) + -> equivalence.relation (t, ctx) (a.subst t ctx (a.sem ctx' op tms) tms') - (a.sem ctx op $ - map (\ty, tm => - a.subst (snd ty) (fst ty ++ ctx) tm - (tabulate {is = fst ty} (a.var . Sublist.elemJoinL {ys = ctx}) ++ - map (\t => a.rename t ([] {ys = fst ty} ++ Relation.reflexive {x = ctx})) tms')) $ - tms) + (a.sem ctx op $ map (a.extendSubst ctx tms') tms) public export record Algebra (0 sig : Signature) where constructor MkAlgebra raw : RawAlgebra sig - 0 relation : IRel (uncurry raw.U) - algebra : IsAlgebra sig raw relation + algebra : IsAlgebra sig raw + +public export 0 +(.relation) : (0 a : Algebra sig) -> (ty : _) -> Rel (uncurry a.raw.U ty) +(.relation) a = a.algebra.equivalence.relation public export -(.setoid) : Algebra sig -> ISetoid (Pair sig.T (List sig.T)) -(.setoid) a = MkISetoid (uncurry a.raw.U) a.relation a.algebra.equivalence +(.setoid) : Algebra sig -> IndexedSetoid (Pair sig.T (List sig.T)) +(.setoid) a = MkIndexedSetoid (uncurry a.raw.U) a.algebra.equivalence public export -(.setoidAt) : Algebra sig -> (ctx : List sig.T) -> ISetoid sig.T -(.setoidAt) a ctx = MkISetoid - (flip a.raw.U ctx) - (\t => a.relation (t, ctx)) - (\_ => a.algebra.equivalence _) +(.setoidAt) : Algebra sig -> (ctx : List sig.T) -> IndexedSetoid sig.T +(.setoidAt) a ctx = reindex (flip MkPair ctx) a.setoid public export -(.varFunc) : (a : Algebra sig) -> (ctx : _) -> IFunction (isetoid (flip Elem ctx)) (a.setoidAt ctx) -(.varFunc) a ctx = MkIFunction - (\_ => a.raw.var) - (\_ => (a.algebra.equivalence _).equalImpliesEq . cong a.raw.var) +(.varFunc) : (a : Algebra sig) -> (ctx : _) -> cast (flip Elem ctx) ~> a.setoidAt ctx +(.varFunc) a ctx = mate (\_ => a.raw.var) public export record IsHomomorphism @@ -139,7 +152,7 @@ record IsHomomorphism -> (tms : extend a.raw.U ctx ^ op.arity) -> b.relation (t, ctx) (f t ctx $ a.raw.sem ctx op tms) - (b.raw.sem ctx op $ map (\ty => f (snd ty) (fst ty ++ ctx)) tms) + (b.raw.sem ctx op $ map (extendFunc f ctx) tms) varHomo : {t : _} -> {ctx : _} -> (i : Elem t ctx) -> b.relation (t, ctx) (f t ctx $ a.raw.var i) (b.raw.var i) substHomo : (t : sig.T) -> (ctx : List sig.T) -> {ctx' : _} -> (tm : a.raw.U t ctx') |