coercions and compositions

lib/Quox/Syntax/Term/TyConKind.idr

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+module Quox.Syntax.Term.TyConKind
+
+import Decidable.Equality
+import Derive.Prelude
+import Generics.Derive
+
+%language ElabReflection
+%default total
+
+
+public export
+data TyConKind = KTYPE | KPi | KSig | KEnum | KEq | KNat | KBOX
+%name TyConKind k
+%runElab derive "TyConKind" [Eq.Eq, Ord.Ord, Show.Show, Generic, Meta, DecEq]
+
+||| a list of all `TyConKind`s
+public export %inline
+allKinds : List TyConKind
+allKinds = %runElab do
+  -- as a script so it stays up to date if there are more tycon kinds
+  cs <- getCons $ fst !(lookupName "TyConKind")
+  traverse (check . var) cs
+
+
+||| in `type-case`, how many variables are bound in this branch
+public export %inline
+arity : TyConKind -> Nat
+arity KTYPE = 0
+arity KPi   = 2
+arity KSig  = 2
+arity KEnum = 0
+arity KEq   = 5
+arity KNat  = 0
+arity KBOX  = 1