Safe Haskell	Safe-Inferred
Language	Haskell2010

Morley.Michelson.Typed.Scope.Internal.Presence

Synopsis

Documentation

data TPresence p t where Source #

Whether a value of this type _may_ contain a type defined by TPredicateSym.

Constructors

TPresent :: ContainsT p t ~ 'True => TPresence p t
TAbsent :: ContainsT p t ~ 'False => TPresence p t

Instances details

Show (TPresence t p) Source #
Instance details Defined in Morley.Michelson.Typed.Scope.Internal.Presence Methods showsPrec :: Int -> TPresence t p -> ShowS # show :: TPresence t p -> String # showList :: [TPresence t p] -> ShowS #

Check for presence of type defined by TPredicateSym at runtime. Use TPredicateSym singletons (i.e. SingTPredicateSym) as the first parameter, e.g.:

>>> checkTPresence SPSOp STOperation
TPresent
>>> checkTPresence SPSOp STUnit
TAbsent

To only prove absence of some type, it is more efficient to use deMorganForbidT or withDeMorganScope.