| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Lorentz.Wrappable
Description
Permissions for casts between wrappers and their inner types.
Synopsis
- class ToT s ~ ToT (Unwrappabled s) => Unwrappable (s :: Type) where
- type Unwrappabled s :: Type
- class Unwrappable s => Wrappable (s :: Type)
Documentation
class ToT s ~ ToT (Unwrappabled s) => Unwrappable (s :: Type) Source #
Declares that this type is just a wrapper over some other type and it can be safely unwrapped to that inner type.
Inspired by lens Wrapped.
Associated Types
type Unwrappabled s :: Type Source #
The type we unwrap to (inner type of the newtype).
Used in constraint for Lorentz instruction wrapping into a Haskell newtype and vice versa.
type Unwrappabled s = GUnwrappabled s (Rep s)
Instances
class Unwrappable s => Wrappable (s :: Type) Source #
Declares that it is safe to wrap an inner type to the given
wrapper type. Can be provided in addition to Unwrappable.
You can declare this instance when your wrapper exists just to
make type system differentiate the two types. Example:
newtype TokenId = TokenId Natural.
Do not define this instance for wrappers that provide some invariants.
Example: UStore type from morley-upgradeable.
Wrappable is similar to lens Wrapped class without the method.
Instances
| Wrappable (ParameterWrapper deriv cp) Source # | |
Defined in Lorentz.Entrypoints.Manual | |
| Wrappable (NamedF Maybe a name) Source # | |
Defined in Lorentz.Wrappable | |
| Wrappable (NamedF Identity a name) Source # | |
Defined in Lorentz.Wrappable | |