shapeless

package shapeless

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package ops
package syntax
package test

Type Members

sealed trait :+:[+H, +T <: Coproduct] extends Coproduct
Like Either, the :+: type defines a new type that can contain either H or T.
final case class ::[+H, +T <: HList](head: H, tail: T) extends HList with Product with Serializable
Non-empty HList element type.
trait <:!<[A, B] extends Serializable
Annotations
@implicitNotFound("${A} must not be a subtype of ${B}")
trait =:!=[A, B] extends Serializable
trait AdditiveCollection[Repr] extends Serializable
Evidence that Repr instances can be nested in a Sized.
Evidence that Repr instances can be nested in a Sized.
Should assert that a Builder[_, Repr] given n elements will result in a Repr of length n.
trait Annotation[A, T] extends Serializable
Evidence that type T has annotation A, and provides an instance of the annotation.
Evidence that type T has annotation A, and provides an instance of the annotation.
If type T has an annotation of type A, then an implicit Annotation[A, T] can be found, and its apply method provides an instance of the annotation.
Example:
```
case class First(i: Int)

@First(3) trait Something


val somethingFirst = Annotation[First, Something].apply()
assert(somethingFirst == First(3))
```
class AnnotationMacros extends CaseClassMacros
Annotations
@bundle()
trait Annotations[A, T] extends DepFn0 with Serializable
Provides the annotations of type A of the fields or constructors of case class-like or sum type T.
Provides the annotations of type A of the fields or constructors of case class-like or sum type T.
If type T is case class-like, this type class inspects its fields and provides their annotations of type A. If type T is a sum type, its constructor types are looked for annotations.
Type Out is an HList having the same number of elements as T (number of fields of T if T is case class-like, or number of constructors of T if it is a sum type). It is made of None.type (no annotation on corresponding field or constructor) and Some[A] (corresponding field or constructor is annotated).
Method apply provides an HList of type Out made of None (corresponding field or constructor not annotated) or Some(annotation) (corresponding field or constructor has annotation annotation).
Note that annotation types must be case class-like for this type class to take them into account.
Example:
```
case class First(s: String)

case class CC(i: Int, @First("a") s: String)

sealed trait Base
@First("b") case class BaseI(i: Int) extends Base
case class BaseS(s: String) extends Base


val ccFirsts = Annotations[First, CC]
val baseFirsts = Annotations[First, Base]

// ccFirsts.Out is  None.type :: Some[First] :: HNil
// ccFirsts.apply() is
//   None :: Some(First("a")) :: HNil

// baseFirsts.Out is  Some[First] :: None.type :: HNil
// baseFirsts.apply() is
//   Some(First("b")) :: None :: HNil
```
class ApplyEverything[F <: Poly] extends AnyRef
trait ApplyUnapplyFacet extends ProductISOFacet
trait BasisConstraint[L <: HList, M <: HList] extends Serializable
Type class witnessing that every element of L is an element of M.
sealed trait CNil extends Coproduct
The CNil type is used to terminate a 'list' of :+: alternatives.
The CNil type is used to terminate a 'list' of :+: alternatives.
Like the Nil constructor of List, it does not convey real information. This is achieved by not having any value for CNil.
This makes the type Int :+: CNil equivalent to Int, because the right (Inr) alternative of :+: can not be constructed properly.
final case class Cached[+T](value: T) extends AnyVal with Product with Serializable
Wraps a cached implicit T.
Wraps a cached implicit T.
Looking for an implicit Cached[T] first triggers a look for an implicit T, caches the resulting tree, and returns it immediately and in subsequent look ups for an implicit Cached[T]. Thus, subsequent look ups do not trigger looking for an implicit T, only returning the instance kept in cache.
Beware that if the contexts in which two subsequent look ups are different, so that looking for a T in each of them doesn't return the same result, this change would be ignored by caching. Looking for a Cached[T] in the first context would put the implicit T of this context in cache, and then looking for a Cached[T] in the second context would return the former instance from the first context. E.g.
```
trait TC[T] {
  def msg: String
}

object First {
  implicit val tc: TC[Int] = new TC[Int] {
    val msg = "first"
  }

  def print() = println(implicitly[TC[Int]].msg)
  def printCached() = println(cached[TC[Int]].msg)
}

object Second {
  implicit val tc: TC[Int] = new TC[Int] {
    val msg = "second"
  }

  def print() = println(implicitly[TC[Int]].msg)
  def printCached() = println(cached[TC[Int]].msg)
}

First.print()
Second.print()
First.printCached()
Second.printCached()
```
would print "first" then "second" (non cached TC[Int] instances), then "first" twice (first instance, returned the second time too through the cache).
class CachedImplicitMacros extends AnyRef
Annotations
@bundle()
class CachedMacros extends LazyMacros with OpenImplicitMacros
Annotations
@bundle()
trait CaseClassFacet extends AnyRef
trait CaseClassMacros extends ReprTypes with CaseClassMacrosVersionSpecifics
Annotations
@bundle()
trait CaseClassMacrosVersionSpecifics extends AnyRef
trait CaseInst extends AnyRef
trait Cases extends AnyRef
type Const[C] = AnyRef { type λ[T] = C }

sealed trait Coproduct extends Product with Serializable

Encodes a coproduct type, such as a sealed family of case classes.

Each constructor from the family gets an encoding in terms of nested Inr and Inl.

Which constructor is encoded as Inl() and which as Inr(Inl()) is determined by lexical order of the subclasses. This example illustrates the encoding:

scala> sealed trait Animal
defined trait Animal

scala> case class Cat(name: String, livesLeft: Int) extends Animal
defined class Cat

scala> case class Dog(name: String, bonesBuried: Int) extends Animal
defined class Dog

scala> case class Koala(name: String, leavesEaten: Int) extends Animal
defined class Koala

scala> case class Sloth(name: String, daysToClimbDownFromCurrentTree: Int) extends Animal
defined class Sloth

scala> val garfield = Cat("Garfield", 9)
garfield: Cat = Cat(Garfield,9)

scala> val odie = Dog("Odie", 3)
odie: Dog = Dog(Odie,3)

scala> val koala = Koala("foo", 10)
koala: Koala = Koala(foo,10)

scala> val sloth = Sloth("bar", 2)
sloth: Sloth = Sloth(bar,2)

scala> val genAnimal = Generic[Animal]
genAnimal: shapeless.Generic[Animal]{type Repr = Cat :+: Dog :+: Koala :+: Sloth} = ...

scala> def showCoproduct(o: Any) : String = o match {
     | case Inl(a) => "Inl(" + showCoproduct(a) + ")"
     | case Inr(a) => "Inr(" + showCoproduct(a) + ")"
     | case a => a.toString
     | }
showCoproduct: (o: Any)String

scala> showCoproduct(genAnimal.to(garfield))
res5: String = Inl(Cat(Garfield,9))

scala> showCoproduct(genAnimal.to(odie))
res6: String = Inr(Inl(Dog(Odie,3)))

scala> showCoproduct(genAnimal.to(koala))
res7: String = Inr(Inr(Inl(Koala(foo,10))))

scala> showCoproduct(genAnimal.to(sloth))
res8: String = Inr(Inr(Inr(Inl(Sloth(bar,2)))))

scala>

trait CopyFacet extends CaseClassFacet
trait Coselect[T] extends AnyRef
trait Data[F, T, R] extends Serializable
Type class representing one-level generic queries.
trait Data0 extends AnyRef
trait Data1 extends Data0
trait DataT[F, T] extends Serializable
Type class representing one-level generic transformations.
trait DataT0 extends AnyRef
trait DataT1 extends DataT0
trait Default[T] extends DepFn0 with Serializable
Provides default values of case class-like types.
Provides default values of case class-like types.
The Out type parameter is an HList type whose length is the number of fields of T. Its elements correspond to the fields of T, in their original order. It is made of None.type (no default value for this field) and Some[...] (default value available for this field, with ... the type of the field). Note that None.type and Some[...] are more precise than simply Option[...], so that the availability of default values can be used in type level calculations.
The apply method returns an HList of type Out, with None elements corresponding to no default value available, and Some(defaultValue) to default value available for the corresponding fields.
Use like
```
case class CC(i: Int, s: String = "b")

val default = Default[CC]

// default.Out is  None.type :: Some[String] :: HNil

// default() returns
//   None :: Some("b") :: HNil,
// typed as default.Out
```
trait DefaultCaseClassDefns extends ApplyUnapplyFacet with ProductFacet with PolymorphicEqualityFacet with CopyFacet with ToStringFacet
class DefaultMacros extends CaseClassMacros
Annotations
@bundle()
trait DefaultSymbolicLabelling[T] extends DepFn0 with Serializable
class DefaultToIndexedSeq[CC[_]] extends AnyRef
trait DepFn0 extends AnyRef
Dependent nullary function type.
trait DepFn1[T] extends AnyRef
Dependent unary function type.
trait DepFn2[T, U] extends AnyRef
Dependent binary function type.
type Everything[F <: Poly, K <: Poly, T] = Case[EverythingAux[F, K], ::[T, HNil]]
The SYB everything combinator
class EverythingAux[F, K] extends Poly
type Everywhere[F <: Poly, T] = Case[EverywhereAux[F], ::[T, HNil]]
The SYB everywhere combinator
class EverywhereAux[F] extends Poly
trait FieldOf[V] extends AnyRef
Field with values of type V.
Field with values of type V.
Record keys of this form should be objects which extend this trait. Keys may also be arbitrary singleton typed values, however keys of this form enforce the type of their values.
trait FieldPoly extends Poly1
Polymorphic function that allows modifications on record fields while preserving the original key types.
trait Fin[N <: Succ[_]] extends AnyRef
Base trait for type level finite numbers, i.e.
Base trait for type level finite numbers, i.e. numbers less than some bound N
case class FinSucc[N <: Succ[_], P <: Fin[N]]() extends Fin[Succ[N]] with Product with Serializable
Encoding of successor.
case class FinZero[N <: Succ[_]]() extends Fin[N] with Product with Serializable
Encoding of zero.
trait FromProductArgs extends Dynamic
Trait supporting mapping HList arguments to argument lists, inverse of ProductArgs.
Trait supporting mapping HList arguments to argument lists, inverse of ProductArgs.
Mixing in this trait enables method applications of the form,
```
lhs.methodProduct(23 :: "foo" :: true)
```
to be rewritten as,
```
lhs.method(23, "foo", true)
```
ie. the HList argument is used to obtain arguments for a target method (the called method named minus the "Product" suffix) in sequence and the application is rewritten to an application of the target method
trait FromRecordArgs extends Dynamic
Trait supporting mapping record arguments to named argument lists, inverse of RecordArgs.
Trait supporting mapping record arguments to named argument lists, inverse of RecordArgs.
Mixing in this trait enables method applications of the form,
```
lhs.methodRecord('x ->> 23 :: 'y ->> "foo" :: 'z ->> true :: HNil)
```
to be rewritten as,
```
lhs.method(x = 23, y = "foo", z = true)
```
ie. the record argument is used to look up arguments for a target method (the called method named minus the "Record" suffix) by name and type and the application is rewritten to an application of the target method
trait Generic[T] extends Serializable
Represents the ability to convert from a concrete type (e.g.
Represents the ability to convert from a concrete type (e.g. a case class) to a generic (HList / Coproduct} based) representation of the type.
For example:
```
scala> sealed trait Animal

defined trait Animal
scala> case class Cat(name: String, livesLeft: Int) extends Animal
defined class Cat

scala> case class Dog(name: String, bonesHidden: Int) extends Animal
defined class Dog

scala> val genCat = Generic[Cat]
genCat: shapeless.Generic[Cat]{ type Repr = String :: Int :: HNil } = ...

scala> val genDog = Generic[Dog]
genDog: shapeless.Generic[Dog]{ type Repr = String :: Int :: HNil } = ...

scala> val garfield = Cat("Garfield", 9)
garfield: Cat = Cat(Garfield,9)

scala> val genGarfield = genCat.to(garfield)
genGarfield: genCat.Repr = Garfield :: 9 :: HNil

scala> val reconstructed = genCat.from(genGarfield)
reconstructed: Cat = Cat(Garfield,9)

scala> reconstructed == garfield
res0: Boolean = true
```
Note that constituents of Cat and Dog are exactly the same - a String and an Int. So we could do:
```
scala> val odieAsCat = genCat.from(genDog.to(odie))
odieAsCat: Cat = Cat(odie,3)
```
This is quite useful in certain cases, such as copying from one object type to another, as in schema evolution.
Note that the generic representation depends on the type at which we instantiate Generic. In the example above we instantiated it at Cat and at Dog, and so the generic representation gave the minimal constituents of each of those.
However, if we instantiate Generic[Animal] instead the generic representation would encode the Cat-ness or Dog-ness of the instance as well (see Coproduct for details of the encoding):
```
scala> genDog.to(odie)
res9: genDog.Repr = odie :: 3 :: HNil

scala> val genAnimal = Generic[Animal]
genAnimal: shapeless.Generic[Animal]{ type Repr = Cat :+: Dog :+: CNil } = ...

scala> genAnimal.to(odie)
res8: genAnimal.Repr = Dog(odie,3)

scala> genAnimal.to(odie) match { case Inr(Inl(dog)) => dog; case _ => null }
res9: Dog = Dog(odie,3)
```
Inr and Inl are shapeless.Coproduct constructors. Shapeless constructs each class representation as a sort of "nested Either" using Coproduct. So in our example, genAnimal would essentially encode garfield as Inl(garfield) and odie as Inr(Inl(odie)). Please see shapeless.Coproduct for more details. }}}
T
An immutable data type that has a canonical way of constructing and deconstructing instances (e.g. via apply / unapply). Sealed families of case classes work best.
trait Generic1[F[_], FR[_[_]]] extends Serializable
trait Generic10 extends AnyRef
class Generic1Macros extends CaseClassMacros
Annotations
@bundle()
class GenericMacros extends CaseClassMacros
Annotations
@bundle()
sealed trait HList extends Product with Serializable
HList ADT base trait.
class HMap[R[_, _]] extends Poly1
Heterogenous map with type-level key/value associations that are fixed by an arbitrary relation R.
Heterogenous map with type-level key/value associations that are fixed by an arbitrary relation R.
HMaps extend Poly and hence are also polymorphic function values with type-specific cases corresponding to the map's type-level key/value associations.
class HMapBuilder[R[_, _]] extends AnyRef
sealed trait HNil extends HList
Empty HList element type.
class HasCoproductGeneric[T] extends Serializable
class HasProductGeneric[T] extends Serializable
type Id[+T] = T
trait InferProduct[C <: Coproduct, K] extends Serializable
final case class Inl[+H, +T <: Coproduct](head: H) extends :+:[H, T] with Product with Serializable
H :+: T can either be H or T.
H :+: T can either be H or T. In this case it is H.
final case class Inr[+H, +T <: Coproduct](tail: T) extends :+:[H, T] with Product with Serializable
H :+: T can either be H or T.
H :+: T can either be H or T. In this case it is T.
trait IsCCons1[L[_], FH[_[_]], FT[_[_]]] extends Serializable
trait IsCCons10 extends AnyRef
class IsCCons1Macros extends IsCons1Macros
Annotations
@bundle()
trait IsCons1Macros extends CaseClassMacros
Annotations
@bundle()
trait IsDistinctConstraint[L <: HList] extends Serializable
Type class witnessing that all elements of L have distinct types
Type class witnessing that all elements of L have distinct types
Annotations
@implicitNotFound("Implicit not found: shapeless.IsDistinctConstraint[${L}]. Some elements have the same type.")
trait IsHCons1[L[_], FH[_[_]], FT[_[_]]] extends Serializable
trait IsHCons10 extends AnyRef
class IsHCons1Macros extends IsCons1Macros
Annotations
@bundle()
class IsTuple[T] extends Serializable
trait KeyConstraint[L <: HList, M <: HList] extends Serializable
Type class witnessing that every element of L is of the form FieldType[K, V] where K is an element of M.
trait LPLens[S, A] extends Dynamic with Serializable
trait LPPath[T <: HList] extends Dynamic
trait LPPrism[S, A] extends Dynamic with Serializable
trait LUBConstraint[L <: HList, B] extends Serializable
Type class witnessing that every element of L is a subtype of B.
trait LabelledGeneric[T] extends Serializable
LabelledGeneric is similar to Generic, but includes information about field names or class names in addition to the raw structure.
LabelledGeneric is similar to Generic, but includes information about field names or class names in addition to the raw structure.
Continuing the example from shapeless.Generic, we use LabelledGeneric to convert an object to an shapeless.HList:
```
scala> val lgenDog = LabelledGeneric[Dog]
lgenDog: shapeless.LabelledGeneric[Dog]{ type Repr = Record.`'name -> String, 'bonesHidden -> Int`.T } = ...

scala> lgenDog.to(odie)
res15: lgenDog.Repr = odie :: 3 :: HNil
```
Note that the representation does not include the labels! The labels are actually encoded in the generic type representation using shapeless.Witness types.
As with shapeless.Generic, the representation for Animal captures the subclass embedding rather than the fields in the class, using shapeless.Coproduct:
```
scala> val lgenAnimal = LabelledGeneric[Animal]
lgenAnimal: shapeless.LabelledGeneric[Animal]{ type Repr = Union.`'Cat -> Cat, 'Dog -> Dog`.T } = ...

scala> lgenAnimal.to(odie)
res16: lgenAnimal.Repr = Dog(odie,3)

scala> genAnimal.to(odie) match { case Inr(Inl(dog)) => dog ; case _ => ???}
res19: Dog = Dog(odie,3)
```
T
the type which this instance can convert to and from a labelled generic representation
class LabelledMacros extends SingletonTypeUtils with CaseClassMacros
Annotations
@bundle()
trait LabelledProductTypeClass[C[_]] extends Serializable
A type class abstracting over the product operation of type classes over types of kind *, as well as deriving instances using an isomorphism.
A type class abstracting over the product operation of type classes over types of kind *, as well as deriving instances using an isomorphism. Refines ProductTypeClass with the addition of runtime String labels corresponding to the names of the product elements.
trait LabelledProductTypeClassCompanion[C[_]] extends Serializable
trait LabelledTypeClass[C[_]] extends LabelledProductTypeClass[C]
A type class additionally abstracting over the coproduct operation of type classes over types of kind *.
A type class additionally abstracting over the coproduct operation of type classes over types of kind *.
Name hints can be safely ignored.
trait LabelledTypeClassCompanion[C[_]] extends LabelledProductTypeClassCompanion[C]

trait Lazy[+T] extends Serializable

Wraps a lazily computed value.

Wraps a lazily computed value. Also circumvents cycles during implicit search, or wrong implicit divergences as illustrated below, and holds the corresponding implicit value lazily.

The following implicit search sometimes fails to compile, because of a wrongly reported implicit divergence,

case class ListCC(list: List[CC])
case class CC(i: Int, s: String)

trait TC[T]

object TC {
  implicit def intTC: TC[Int] = ???
  implicit def stringTC: TC[String] = ???
  implicit def listTC[T](implicit underlying: TC[T]): TC[List[T]] = ???

  implicit def genericTC[F, G](implicit
    gen: Generic.Aux[F, G],
    underlying: TC[G]
  ): TC[F] = ???

  implicit def hnilTC: TC[HNil] = ???

  implicit def hconsTC[H, T <: HList](implicit
    headTC: TC[H],
    tailTC: TC[T]
  ): TC[H :: T] = ???
}

implicitly[TC[ListCC]] // fails with: diverging implicit expansion for type TC[ListCC]

This wrongly reported implicit divergence can be circumvented by wrapping some of the implicit values in Lazy,

case class ListCC(list: List[CC])
case class CC(i: Int, s: String)

trait TC[T]

object TC {
  implicit def intTC: TC[Int] = ???
  implicit def stringTC: TC[String] = ???
  implicit def listTC[T](implicit underlying: TC[T]): TC[List[T]] = ???

  implicit def genericTC[F, G](implicit
    gen: Generic.Aux[F, G],
    underlying: Lazy[TC[G]] // wrapped in Lazy
  ): TC[F] = ???

  implicit def hnilTC: TC[HNil] = ???

  implicit def hconsTC[H, T <: HList](implicit
    headTC: Lazy[TC[H]], // wrapped in Lazy
    tailTC: TC[T]
  ): TC[H :: T] = ???
}

implicitly[TC[ListCC]]

When looking for an implicit Lazy[TC[T]], the Lazy.mkLazy macro will itself trigger the implicit search for a TC[T]. If this search itself triggers searches for types wrapped in Lazy, these will be done only once, their result put in a lazy val, and a reference to this lazy val will be returned as the corresponding value. It will then wrap all the resulting values together, and return a reference to the first one.

E.g. with the above example definitions, when looking up for an implicit TC[ListCC], the returned tree roughly looks like

TC.genericTC(
  Generic[ListCC], // actually, the tree returned by Generic.materialize, not written here for the sake of brevity
  Lazy {
    lazy val impl1: TC[List[CC] :: HNil] = TC.hconsTC(
      Lazy(impl2),
      TC.hnilTC
    )
    lazy val impl2: TC[List[CC]] = TC.listTC(TC.genericTC(
      Generic[CC], // actually, the tree returned by Generic.materialize
      Lazy(impl1)  // cycles to the initial TC[List[CC] :: HNil]
    ))

    impl1
  }
)

Annotations: @implicitNotFound("could not find Lazy implicit value of type ${T}")

class LazyMacros extends CaseClassMacros with OpenImplicitMacros with LowPriorityTypes
Annotations
@bundle()
trait LazyMacrosCompat extends AnyRef
class LazyMacrosRef extends AnyRef
trait Lens[S, A] extends LPLens[S, A]
sealed trait LowPriority extends Serializable
Evidence that no implicit instance of the same type as the one being currently searched is available elsewhere.
Evidence that no implicit instance of the same type as the one being currently searched is available elsewhere.
Added to an implicit def like
```
implicit def genericThing[F, G]
 (implicit
   ev: LowPriority,
   gen: Generic.Aux[F, G],
   underlying: Thing[G]
 ): Thing[F] = ???
```
it prevents genericThing to provide an instance of Thing[F] if an implicit one is already available elsewhere. This effectively gives genericThing a lower priority than the already existing implicits - without having to deal with cumbersome priority scoping.
class LowPriorityMacros extends OpenImplicitMacros with LowPriorityTypes
Annotations
@bundle()
trait LowPriorityMkPathOptic extends AnyRef
trait LowPriorityMkSelectDynamicOptic extends AnyRef
trait LowPrioritySegment extends AnyRef
trait LowPrioritySized extends AnyRef
trait LowPriorityTypeable extends AnyRef
trait LowPriorityTypes extends AnyRef
Annotations
@bundle()
trait LowPriorityUnaryTCConstraint extends LowPriorityUnaryTCConstraint0
trait LowPriorityUnaryTCConstraint0 extends AnyRef
trait LowPriorityUnwrappedInstances extends AnyRef
trait LowPriorityWitnessWith extends AnyRef
trait Lub[-A, -B, Out] extends Serializable
Type class witnessing the least upper bound of a pair of types and providing conversions from each to their common supertype.
trait MkCoproductSelectPrism[C <: Coproduct, T] extends Serializable
trait MkCtorPrism[A, B] extends Serializable
trait MkFieldLens[A, K] extends Serializable
trait MkGenericLens[T] extends Serializable
trait MkHListNthLens[L <: HList, N <: Nat] extends Serializable
trait MkHListSelectLens[L <: HList, U] extends Serializable
trait MkLabelledGenericLens[T] extends Serializable
trait MkNthFieldLens[A, N <: Nat] extends Serializable
trait MkPathOptic[S, P <: HList] extends Serializable
trait MkRecordSelectLens[R <: HList, K] extends Serializable
trait MkSelectDynamicOptic[R, A, K, B] extends Serializable
trait Nat extends AnyRef
Base trait for type level natural numbers.
trait NatMacroDefns extends AnyRef
Annotations
@bundle()
class NatMacros extends NatMacroDefns
Annotations
@bundle()
trait NatProductArgs extends Dynamic
Trait supporting mapping dynamic argument lists of Ints to HList of Nat arguments.
Trait supporting mapping dynamic argument lists of Ints to HList of Nat arguments.
Mixing in this trait enables method applications of the form,
```
lhs.method(1, 2, 3)
```
to be rewritten as,
```
lhs.methodProduct(_1 :: _2 :: _3)
```
ie. the arguments are rewritten as HList elements of Nat and the application is rewritten to an application of an implementing method (identified by the "Product" suffix) which accepts a single HList of Int argument.
trait NatTRel0 extends AnyRef
trait NatWith[TC[_ <: Nat]] extends AnyRef
trait Nats extends AnyRef
trait NotContainsConstraint[L <: HList, U] extends Serializable
Type class witnessing that L doesn't contain elements of type U
Type class witnessing that L doesn't contain elements of type U
Annotations
@implicitNotFound("Implicit not found: shapeless.NotContainsConstraint[${L}, ${U}]. This HList already contains element of type ${U}.")
trait OpenImplicitMacros extends AnyRef
Annotations
@bundle()
trait OpticComposer[L, R] extends Serializable
sealed trait OrElse[+A, +B] extends AnyRef
Like Option.orElse on the type level and like Either on the value level.
Like Option.orElse on the type level and like Either on the value level.
Instead of left and right constructors OrElse has primary and secondary implicits that lazily try to resolve first a value of type A or otherwise a value of type B.
case class Orphan[F[_], D, T](instance: F[T]) extends Product with Serializable
trait OrphanDeriver[F[_], D] extends AnyRef
class OrphanMacros extends CaseClassMacros
Annotations
@bundle()
trait Path[T <: HList] extends LPPath[T]
trait Poly extends PolyApply with Serializable
Base trait for polymorphic values.
trait Poly0 extends Poly
Trait simplifying the creation of polymorphic values.
trait Poly1 extends Poly
trait Poly10 extends Poly
trait Poly11 extends Poly
trait Poly12 extends Poly
trait Poly13 extends Poly
trait Poly14 extends Poly
trait Poly15 extends Poly
trait Poly16 extends Poly
trait Poly17 extends Poly
trait Poly18 extends Poly
trait Poly19 extends Poly
trait Poly2 extends Poly
trait Poly20 extends Poly
trait Poly21 extends Poly
trait Poly22 extends Poly
trait Poly3 extends Poly
trait Poly4 extends Poly
trait Poly5 extends Poly
trait Poly6 extends Poly
trait Poly7 extends Poly
trait Poly8 extends Poly
trait Poly9 extends Poly
trait PolyApply extends AnyRef
trait PolyInst extends AnyRef
class PolyMacros extends AnyRef
Annotations
@bundle()
trait PolymorphicEqualityFacet extends ProductISOFacet
final class Primary[+A] extends OrElse[A, Nothing]
trait Prism[S, A] extends LPPrism[S, A]
trait ProductArgs extends Dynamic
Trait supporting mapping dynamic argument lists to HList arguments.
Trait supporting mapping dynamic argument lists to HList arguments.
Mixing in this trait enables method applications of the form,
```
lhs.method(23, "foo", true)
```
to be rewritten as,
```
lhs.methodProduct(23 :: "foo" :: true)
```
ie. the arguments are rewritten as HList elements and the application is rewritten to an application of an implementing method (identified by the "Product" suffix) which accepts a single HList argument.
trait ProductFacet extends ProductISOFacet
trait ProductISOFacet extends CaseClassFacet
trait ProductLensBuilder[C, P <: Product] extends Lens[C, P] with Serializable
class ProductMacros extends SingletonTypeUtils with NatMacroDefns
Annotations
@bundle()
trait ProductPrismBuilder[C, P <: Product] extends Prism[C, P] with Serializable
trait ProductTypeClass[C[_]] extends Serializable
A type class abstracting over the product operation of type classes over types of kind *, as well as deriving instances using an isomorphism.
trait ProductTypeClassCompanion[C[_]] extends Serializable
trait RecordArgs extends Dynamic
Trait supporting mapping named argument lists to record arguments.
Trait supporting mapping named argument lists to record arguments.
Mixing in this trait enables method applications of the form,
```
lhs.method(x = 23, y = "foo", z = true)
```
to be rewritten as,
```
lhs.methodRecord('x ->> 23 :: 'y ->> "foo", 'z ->> true)
```
ie. the named arguments are rewritten as record fields with the argument name encoded as a singleton-typed Symbol and the application is rewritten to an application of an implementing method (identified by the "Record" suffix) which accepts a single record argument.
class RecordMacros extends AnyRef
Annotations
@bundle()
trait Refute[T] extends AnyRef
Evidence that no implicit instance of type T is available
trait ReprTypes extends AnyRef
Annotations
@bundle()
trait ScalaVersionSpecifics extends AnyRef
final class Secondary[+B] extends OrElse[Nothing, B]
trait Segment[P, S, T <: HList] extends AnyRef
trait Select[T] extends AnyRef
trait SingletonProductArgs extends Dynamic
Trait supporting mapping dynamic argument lists to singleton-typed HList arguments.
Trait supporting mapping dynamic argument lists to singleton-typed HList arguments.
Mixing in this trait enables method applications of the form,
```
lhs.method(23, "foo", true)
```
to be rewritten as,
```
lhs.methodProduct(23.narrow :: "foo".narrow :: true.narrow)
```
ie. the arguments are rewritten as singleton-typed HList elements and the application is rewritten to an application of an implementing method (identified by the "Product" suffix) which accepts a single HList argument.
class SingletonTypeMacros extends SingletonTypeUtils with NatMacroDefns
Annotations
@bundle()
trait SingletonTypeUtils extends ReprTypes
Annotations
@bundle()
final class Sized[+Repr, L <: Nat] extends AnyRef
Wrapper for a collection type witnessing that it has the statically specified length.
Wrapper for a collection type witnessing that it has the statically specified length. Can be applied to any type which can be viewed as an IterableOps, ie. standard collections, Arrays, Strings etc.
class SizedBuilder[CC[_]] extends AnyRef
class SizedOps[A0, Repr, L <: Nat] extends AnyRef
Carrier for Sized operations.
Carrier for Sized operations.
These operations are implemented here as extension methods of the minimal Sized type to avoid issues that would otherwise be caused by its covariance.
trait Split1[L[_], FO[_[_]], FI[_[_]]] extends Serializable
trait Split10 extends AnyRef
class Split1Macros extends CaseClassMacros
Annotations
@bundle()
trait Strict[+T] extends Serializable
Wraps an eagerly computed value.
Wraps an eagerly computed value. Prevents wrongly reported implicit divergence, like Lazy does, but, unlike it, does not circumvent implicit cycles.
Creation of Lazy instances usually triggers the creation of an anonymous class, to compute the wrapped value (e.g. with the by-name argument of Lazy.apply). Strict avoids that, which can lead to less overhead during compilation.
case class Succ[P <: Nat]() extends Nat with Product with Serializable
Encoding of successor.
class TestMacros extends AnyRef
Annotations
@bundle()
class TheMacros extends AnyRef
Annotations
@bundle()
trait ToStringFacet extends ProductFacet
trait TupleTypeableInstances extends AnyRef
trait TypeCase[T] extends Serializable
Extractor for use of Typeable in pattern matching.
Extractor for use of Typeable in pattern matching.
Thanks to Stacy Curl for the idea.
trait TypeClass[C[_]] extends ProductTypeClass[C]
A type class additionally abstracting over the coproduct operation of type classes over types of kind *.
trait TypeClassCompanion[C[_]] extends ProductTypeClassCompanion[C]
trait Typeable[T] extends Serializable
Type class supporting type safe cast.
class TypeableMacros extends SingletonTypeUtils
Annotations
@bundle()
trait UnaryTCConstraint[L <: HList, TC[_]] extends Serializable
Type class witnessing that every element of L has TC as its outer type constructor.
class UnionMacros extends AnyRef
Annotations
@bundle()
trait Unpack1[-PP, FF[_], A] extends AnyRef
Type class witnessing that type PP is equal to FF[A] for some higher kinded type FF[_] and type(s) A.
trait Unpack10[-PP, FF[_, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J.
trait Unpack11[-PP, FF[_, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K.
trait Unpack12[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L.
trait Unpack13[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M.
trait Unpack14[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N.
trait Unpack15[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O.
trait Unpack16[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P.
trait Unpack17[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q.
trait Unpack18[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R.
trait Unpack19[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S.
trait Unpack2[-PP, FF[_, _], A, B] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B] for some higher kinded type FF[_, _] and type(s) A, B.
trait Unpack20[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T.
trait Unpack21[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U.
trait Unpack22[-PP, FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] for some higher kinded type FF[_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V.
trait Unpack3[-PP, FF[_, _, _], A, B, C] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C] for some higher kinded type FF[_, _, _] and type(s) A, B, C.
trait Unpack4[-PP, FF[_, _, _, _], A, B, C, D] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D] for some higher kinded type FF[_, _, _, _] and type(s) A, B, C, D.
trait Unpack5[-PP, FF[_, _, _, _, _], A, B, C, D, E] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E] for some higher kinded type FF[_, _, _, _, _] and type(s) A, B, C, D, E.
trait Unpack6[-PP, FF[_, _, _, _, _, _], A, B, C, D, E, F] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F] for some higher kinded type FF[_, _, _, _, _, _] and type(s) A, B, C, D, E, F.
trait Unpack7[-PP, FF[_, _, _, _, _, _, _], A, B, C, D, E, F, G] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G] for some higher kinded type FF[_, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G.
trait Unpack8[-PP, FF[_, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H] for some higher kinded type FF[_, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H.
trait Unpack9[-PP, FF[_, _, _, _, _, _, _, _, _], A, B, C, D, E, F, G, H, I] extends AnyRef
Type class witnessing that type PP is equal to FF[A, B, C, D, E, F, G, H, I] for some higher kinded type FF[_, _, _, _, _, _, _, _, _] and type(s) A, B, C, D, E, F, G, H, I.
trait Unwrapped[W] extends Serializable
trait UnwrappedInstances extends LowPriorityUnwrappedInstances
trait ValueConstraint[L <: HList, M <: HList] extends Serializable
Type class witnessing that every element of L is of the form FieldType[K, V] where V is an element of M.
trait Widen[T] extends DepFn1[T]
Provides the widen type of a singleton type.
Provides the widen type of a singleton type.
Type member Out of an implicitly available Witness[T] instance is the widen type of T, and the apply method explicitly converts a T to an Out.
E.g. if T is Witness.2.T, Out is Int.
It somehow complements Witness, providing the corresponding non-witnessed standard type, if any.
Example of use, {{ val w = Widen[Witness.2.T] // w.Out is Int // w(2) is typed as Int }}
trait Witness extends Serializable
Provides the value corresponding to a singleton type.
Provides the value corresponding to a singleton type.
See SIP-23 for a related proposed language change.
trait WitnessWith[TC[_]] extends Witness
case class WrappedOrphan[T](instance: T) extends Product with Serializable
case class Zipper[C, L <: HList, R <: HList, P](prefix: L, suffix: R, parent: P) extends Product with Serializable
Generic Zipper for any type with a representation via Generic.
class _0 extends Nat with Serializable
Encoding of zero.
class nonGeneric extends scala.annotation.Annotation with StaticAnnotation
type |¬|[T] = AnyRef { type λ[U] = U <:!< T }
type |∨|[T, U] = AnyRef { type λ[X] = shapeless.package.¬¬[X] <:< (T ∨ U) }
class ~?>[K[_], V[_]] extends Serializable
Type class witnessing the existence of a natural transformation between K[_] and V[_].
Type class witnessing the existence of a natural transformation between K[_] and V[_].
Use this trait to represent an HMap relation of the form K[T] maps to V[T].
type ¬[T] = (T) => Nothing
type ¬¬[T] = (¬[T]) => Nothing
type ∀[P[_]] = (∃[[X](P[X]) => Nothing]) => Nothing
type ∃[P[_]] = P[_]
type ∧[T, U] = T with U
type ∨[T, U] = (∧[¬[T], ¬[U]]) => Nothing

Value Members

val ^: Path.type
macro def cachedImplicit[T]: T
def everything(f: Poly): ApplyEverything[f.type]
def everywhere(f: Poly): EverywhereAux[f.type]
val fin: Fin.type
'Fin'
val lens: OpticDefns.type
val nat: Nat.type
Nat literals
implicit def neq[A, B]: =:!=[A, B]
implicit def neqAmbig1[A]: =:!=[A, A]
implicit def neqAmbig2[A]: =:!=[A, A]
implicit def nsub[A, B]: <:!<[A, B]
implicit def nsubAmbig1[A, B >: A]: <:!<[A, B]
implicit def nsubAmbig2[A, B >: A]: <:!<[A, B]
val optic: OpticDefns.type
Optic definitions
val poly: PolyDefns.type
Poly definitions
val prism: OpticDefns.type
def unexpected: Nothing
object AdditiveCollection extends Serializable
object Annotation extends Serializable
object Annotations extends Serializable
object BasisConstraint extends Serializable
object BuildInfo extends Product with Serializable
This object was generated by sbt-buildinfo.
object Cached extends Serializable
object CachedMacros
object Coproduct extends Dynamic with Serializable
object Data extends Data1 with Serializable
object DataT extends DataT1 with Serializable
object Default extends Serializable
object DefaultSymbolicLabelling extends Serializable
object DefaultToIndexedSeq
object EverythingAux extends Serializable
object EverywhereAux extends Serializable
object Fin
object Generic extends Serializable
The companion object for the Generic trait provides a way of obtaining a Generic[T] instance for some T.
The companion object for the Generic trait provides a way of obtaining a Generic[T] instance for some T. In addition, it defines Generic.Aux, which is an important implementation technique that can be generally useful.
object Generic1 extends Generic10 with Serializable
object HList extends Dynamic with Serializable
object HMap extends Serializable
object HNil extends HNil with Product with Serializable
Empty HList value.
object HasCoproductGeneric extends Serializable
object HasProductGeneric extends Serializable
object InferProduct extends Serializable
object IsCCons1 extends IsCCons10 with Serializable
object IsDistinctConstraint extends Serializable
object IsHCons1 extends IsHCons10 with Serializable
object IsTuple extends Serializable
object KeyConstraint extends Serializable
object LUBConstraint extends Serializable
object LabelledGeneric extends Serializable
object Lazy extends Serializable
object LazyMacros extends LazyMacrosCompat
object LowPriority extends Serializable
object Lub extends Serializable
object MkCoproductSelectPrism extends Serializable
object MkCtorPrism extends Serializable
object MkFieldLens extends Serializable
object MkGenericLens extends Serializable
object MkHListNthLens extends Serializable
object MkHListSelectLens extends Serializable
object MkLabelledGenericLens extends Serializable
object MkNthFieldLens extends Serializable
object MkPathOptic extends LowPriorityMkPathOptic with Serializable
object MkRecordSelectLens extends Serializable
object MkSelectDynamicOptic extends LowPriorityMkSelectDynamicOptic with Serializable
object Nat extends Nats
Type level encoding of the natural numbers.
object NatWith
object NotContainsConstraint extends Serializable
object OpticComposer extends Serializable
object OpticDefns
object OrElse extends OrElse0
object Orphan extends Serializable
object Path extends Path[HNil]
object Poly extends PolyInst with Serializable
Provides implicit conversions from polymorphic function values to monomorphic function values, eg.
Provides implicit conversions from polymorphic function values to monomorphic function values, eg. for use as arguments to ordinary higher order functions.
object Poly1 extends Poly1Builder[HNil] with Serializable
object Poly10 extends Poly10Builder[HNil] with Serializable
object Poly11 extends Poly11Builder[HNil] with Serializable
object Poly12 extends Poly12Builder[HNil] with Serializable
object Poly13 extends Poly13Builder[HNil] with Serializable
object Poly14 extends Poly14Builder[HNil] with Serializable
object Poly15 extends Poly15Builder[HNil] with Serializable
object Poly16 extends Poly16Builder[HNil] with Serializable
object Poly17 extends Poly17Builder[HNil] with Serializable
object Poly18 extends Poly18Builder[HNil] with Serializable
object Poly19 extends Poly19Builder[HNil] with Serializable
object Poly2 extends Poly2Builder[HNil] with Serializable
object Poly20 extends Poly20Builder[HNil] with Serializable
object Poly21 extends Poly21Builder[HNil] with Serializable
object Poly22 extends Poly22Builder[HNil] with Serializable
object Poly3 extends Poly3Builder[HNil] with Serializable
object Poly4 extends Poly4Builder[HNil] with Serializable
object Poly5 extends Poly5Builder[HNil] with Serializable
object Poly6 extends Poly6Builder[HNil] with Serializable
object Poly7 extends Poly7Builder[HNil] with Serializable
object Poly8 extends Poly8Builder[HNil] with Serializable
object Poly9 extends Poly9Builder[HNil] with Serializable
object PolyDefns extends Cases
object PolyNBuilders
Provides elegant syntax for creating polys from functions
object Refute
object Segment extends LowPrioritySegment
object Sized extends LowPrioritySized
object Split1 extends Split10 with Serializable
object Strict extends Serializable
object Tuple
object TypeCase extends Serializable
object TypeOf extends Dynamic
object Typeable extends TupleTypeableInstances with LowPriorityTypeable with Serializable
Provides instances of Typeable.
Provides instances of Typeable. Also provides an implicit conversion which enhances arbitrary values with a cast[T] method.
object UnaryTCConstraint extends LowPriorityUnaryTCConstraint with Serializable
object Unpack1
object Unpack10
object Unpack11
object Unpack12
object Unpack13
object Unpack14
object Unpack15
object Unpack16
object Unpack17
object Unpack18
object Unpack19
object Unpack2
object Unpack20
object Unpack21
object Unpack22
object Unpack3
object Unpack4
object Unpack5
object Unpack6
object Unpack7
object Unpack8
object Unpack9
object Unwrapped extends UnwrappedInstances with Serializable
object ValueConstraint extends Serializable
object Widen
object Witness extends Dynamic with Serializable
object WitnessWith extends LowPriorityWitnessWith with Serializable
object WrappedOrphan extends Serializable
object Zipper extends Serializable
object labelled
object lazily
object newtype
object productElements extends Poly1
Higher ranked function which converts products to HLists.
object record
Record operations on HList's with field-like elements.
object tag

object the extends Dynamic

An enhanced alternative to Predef.implicitly.

Used as a term the[T] yields the unique implicit value of type T in the current implicit scope, if any. It is a compile time error if there is no such value. Its primary advantage over Predef.implicitly is that it will preserve any refinement that the implicit definition has, resulting in more precisely typed, and hence often more useful, values,

scala> trait Foo { type T ; val t: T }
defined trait Foo

scala> implicit val intFoo: Foo { type T = Int } = new Foo { type T = Int ; val t = 23 }
intFoo: Foo{type T = Int} = $anon$1@6067b682

scala> implicitly[Foo].t  // implicitly loses precision
res0: Foo#T = 23

scala> implicitly[Foo].t+13
<console>:13: error: type mismatch;
 found   : Int(13)
 required: String
              implicitly[Foo].t+13
                                ^

scala> the[Foo].t         // the retains it
res1: Int = 23

scala> the[Foo].t+13
res2: Int = 36

Unlike implicitly, the can also be used in type position, thanks to a trick due to Denys Shabalin (@den_sh) and Eugene Burmako (@xeno_by). Here we use a combination of selectDynamic and backticks to embed a type in a path which appears to the compiler as stable,

scala> val i: implicitly[Foo].T = 23  // syntax error
<console>:1: error: ';' expected but '.' found.
       val i: implicitly[Foo].T = 23
                             ^
scala> val i: the.`Foo`.T = 23        // OK
i: Int = 23

object tupled extends Poly1
Higher ranked function which converts HLists to tuples.
object union
object ~?> extends NatTRel0 with Serializable

Packages

shapeless

package shapeless

Package Members

Type Members

Value Members

Inherited from ScalaVersionSpecifics

Inherited from AnyRef

Inherited from Any

Ungrouped

Packages

shapeless

package shapeless

Package Members

Type Members

Value Members

Inherited from ScalaVersionSpecifics

Inherited from AnyRef

Inherited from Any

Ungrouped

shapeless