Trait scala.reflect.api.Internals.InternalApi

trait InternalApi extends AnyRef

Reflection API exhibits a tension inherent to experimental things: on the one hand we want it to grow into a beautiful and robust API, but on the other hand we have to deal with immaturity of underlying mechanisms by providing not very pretty solutions to enable important use cases.

In Scala 2.10, which was our first stab at reflection API, we didn't have a systematic approach to dealing with this tension, sometimes exposing too much of internals (e.g. Symbol.deSkolemize) and sometimes exposing too little (e.g. there's still no facility to change owners, to do typing transformations, etc). This resulted in certain confusion with some internal APIs living among public ones, scaring the newcomers, and some internal APIs only available via casting, which requires intimate knowledge of the compiler and breaks compatibility guarantees.

This led to creation of the internal API module for the reflection API, which provides advanced APIs necessary for macros that push boundaries of the state of the art, clearly demarcating them from the more or less straightforward rest and providing compatibility guarantees on par with the rest of the reflection API (full compatibility within minor releases, best effort towards backward compatibility within major releases, clear replacement path in case of rare incompatible changes in major releases).

The internal module itself (the value that implements InternalApi) isn't defined here, in scala.reflect.api.Universe, but is provided on per-implementation basis. Runtime API endpoint (scala.reflect.runtime.universe) provides universe.compat: InternalApi, whereas compile-time API endpoints (instances of scala.reflect.macros.Context) provide c.compat: ContextInternalApi, which extends InternalApi with additional universe-specific and context-specific functionality.

Self Type
Universe.InternalApi
Source
Internals.scala
Linear Supertypes
Known Subclasses

Type Members

trait DecoratorApi extends AnyRef

See also

Decorators

abstract type Decorators <: DecoratorApi

Abstract Value Members

abstract def annotatedType(annotations: List[Universe.Annotation], underlying: Universe.Type): Universe.AnnotatedType

abstract def asFreeTerm(symbol: Universe.Symbol): Universe.FreeTermSymbol

This symbol cast to a free term symbol.

Exceptions thrown

ScalaReflectionException if isFreeTerm is false.

abstract def asFreeType(symbol: Universe.Symbol): Universe.FreeTypeSymbol

This symbol cast to a free type symbol.

Exceptions thrown

ScalaReflectionException if isFreeType is false.

abstract def boundedWildcardType(bounds: Universe.TypeBounds): Universe.BoundedWildcardType

abstract def classDef(sym: Universe.Symbol, impl: Universe.Template): Universe.ClassDef

abstract def classInfoType(parents: List[Universe.Type], decls: Universe.Scope, typeSymbol: Universe.Symbol): Universe.ClassInfoType

abstract def constantType(value: Universe.Constant): Universe.ConstantType

abstract def createImporter(from0: Universe): Universe.Importer { val from: from0.type }

Creates an importer that moves reflection artifacts between universes.

See also

Importer

abstract def deSkolemize(symbol: Universe.Symbol): Universe.Symbol

If this symbol is a skolem, its corresponding type parameter, otherwise the symbol itself.

To quote Martin Odersky, skolems are synthetic type "constants" that are copies of existentially bound or universally bound type variables. E.g. if one is inside the right-hand side of a method:

def foo[T](x: T) = ... foo[List[T]]....

the skolem named T refers to the unknown type instance of T when foo is called. It needs to be different from the type parameter because in a recursive call as in the foo[List[T]] above the type parameter gets substituted with List[T], but the type skolem stays what it is.

The other form of skolem is an existential skolem. Say one has a function

def bar(xs: List[T] forSome { type T }) = xs.head

then each occurrence of xs on the right will have type List[T'] where T' is a fresh copy of T.

abstract val decorators: Decorators

See also

Decorators

abstract def defDef(sym: Universe.Symbol, rhs: (List[List[Universe.Symbol]]) ⇒ Universe.Tree): Universe.DefDef

abstract def defDef(sym: Universe.Symbol, rhs: Universe.Tree): Universe.DefDef

abstract def defDef(sym: Universe.Symbol, mods: Universe.Modifiers, rhs: Universe.Tree): Universe.DefDef

abstract def defDef(sym: Universe.Symbol, vparamss: List[List[Universe.ValDef]], rhs: Universe.Tree): Universe.DefDef

abstract def defDef(sym: Universe.Symbol, mods: Universe.Modifiers, vparamss: List[List[Universe.ValDef]], rhs: Universe.Tree): Universe.DefDef

abstract def existentialAbstraction(tparams: List[Universe.Symbol], tpe0: Universe.Type): Universe.Type

A creator for existential types. This generates:

tpe1 where { tparams }

where tpe1 is the result of extrapolating tpe with regard to tparams. Extrapolating means that type variables in tparams occurring in covariant positions are replaced by upper bounds, (minus any SingletonClass markers), type variables in tparams occurring in contravariant positions are replaced by upper bounds, provided the resulting type is legal with regard to stability, and does not contain any type variable in tparams.

The abstraction drops all type parameters that are not directly or indirectly referenced by type tpe1. If there are no remaining type parameters, simply returns result type tpe.

abstract def existentialType(quantified: List[Universe.Symbol], underlying: Universe.Type): Universe.ExistentialType

abstract def flags(symbol: Universe.Symbol): Universe.FlagSet

abstract def freeTerms(tree: Universe.Tree): List[Universe.FreeTermSymbol]

abstract def freeTypes(tree: Universe.Tree): List[Universe.FreeTypeSymbol]

abstract def fullyInitialize(scope: Universe.Scope): scope.type

abstract def fullyInitialize(tp: Universe.Type): tp.type

abstract def fullyInitialize(symbol: Universe.Symbol): symbol.type

abstract def initialize(symbol: Universe.Symbol): symbol.type

Forces all outstanding completers associated with this symbol. After this call returns, the symbol becomes immutable and thread-safe.

abstract def intersectionType(tps: List[Universe.Type], owner: Universe.Symbol): Universe.Type

A creator for intersection type where intersections of a single type are replaced by the type itself, and repeated parent classes are merged.

!!! Repeated parent classes are not merged - is this a bug in the comment or in the code?

abstract def intersectionType(tps: List[Universe.Type]): Universe.Type

abstract def isErroneous(symbol: Universe.Symbol): Boolean

abstract def isFreeTerm(symbol: Universe.Symbol): Boolean

abstract def isFreeType(symbol: Universe.Symbol): Boolean

abstract def isSkolem(symbol: Universe.Symbol): Boolean

abstract def labelDef(sym: Universe.Symbol, params: List[Universe.Symbol], rhs: Universe.Tree): Universe.LabelDef

abstract def methodType(params: List[Universe.Symbol], resultType: Universe.Type): Universe.MethodType

abstract def moduleDef(sym: Universe.Symbol, impl: Universe.Template): Universe.ModuleDef

abstract def newClassSymbol(owner: Universe.Symbol, name: Universe.TypeName, pos: Universe.Position = NoPosition, flags: Universe.FlagSet = NoFlags): Universe.ClassSymbol

abstract def newFreeTerm(name: String, value: ⇒ Any, flags: Universe.FlagSet = NoFlags, origin: String = null): Universe.FreeTermSymbol

abstract def newFreeType(name: String, flags: Universe.FlagSet = NoFlags, origin: String = null): Universe.FreeTypeSymbol

abstract def newMethodSymbol(owner: Universe.Symbol, name: Universe.TermName, pos: Universe.Position = NoPosition, flags: Universe.FlagSet = NoFlags): Universe.MethodSymbol

abstract def newModuleAndClassSymbol(owner: Universe.Symbol, name: Universe.Name, pos: Universe.Position = NoPosition, flags: Universe.FlagSet = NoFlags): (Universe.ModuleSymbol, Universe.ClassSymbol)

abstract def newScopeWith(elems: Universe.Symbol*): Universe.Scope

abstract def newTermSymbol(owner: Universe.Symbol, name: Universe.TermName, pos: Universe.Position = NoPosition, flags: Universe.FlagSet = NoFlags): Universe.TermSymbol

abstract def newTypeSymbol(owner: Universe.Symbol, name: Universe.TypeName, pos: Universe.Position = NoPosition, flags: Universe.FlagSet = NoFlags): Universe.TypeSymbol

abstract def nullaryMethodType(resultType: Universe.Type): Universe.NullaryMethodType

abstract def polyType(tparams: List[Universe.Symbol], tpe: Universe.Type): Universe.PolyType

A creator for type parameterizations that strips empty type parameter lists. Use this factory method to indicate the type has kind * (it's a polymorphic value) until we start tracking explicit kinds equivalent to typeFun (except that the latter requires tparams nonEmpty).

abstract def refinedType(parents: List[Universe.Type], owner: Universe.Symbol, decls: Universe.Scope, pos: Universe.Position): Universe.Type

abstract def refinedType(parents: List[Universe.Type], owner: Universe.Symbol, decls: Universe.Scope): Universe.Type

abstract def refinedType(parents: List[Universe.Type], owner: Universe.Symbol): Universe.Type

abstract def refinedType(parents: List[Universe.Type], decls: Universe.Scope, clazz: Universe.Symbol): Universe.RefinedType

abstract def refinedType(parents: List[Universe.Type], decls: Universe.Scope): Universe.RefinedType

abstract val reificationSupport: Universe.ReificationSupportApi

abstract def singleType(pre: Universe.Type, sym: Universe.Symbol): Universe.Type

abstract def substituteSymbols(tree: Universe.Tree, from: List[Universe.Symbol], to: List[Universe.Symbol]): Universe.Tree

abstract def substituteThis(tree: Universe.Tree, clazz: Universe.Symbol, to: ⇒ Universe.Tree): Universe.Tree

abstract def substituteTypes(tree: Universe.Tree, from: List[Universe.Symbol], to: List[Universe.Type]): Universe.Tree

abstract def superType(thistpe: Universe.Type, supertpe: Universe.Type): Universe.Type

abstract def thisType(sym: Universe.Symbol): Universe.Type

abstract def typeBounds(lo: Universe.Type, hi: Universe.Type): Universe.TypeBounds

abstract def typeDef(sym: Universe.Symbol): Universe.TypeDef

abstract def typeDef(sym: Universe.Symbol, rhs: Universe.Tree): Universe.TypeDef

abstract def typeRef(pre: Universe.Type, sym: Universe.Symbol, args: List[Universe.Type]): Universe.Type

abstract def valDef(sym: Universe.Symbol): Universe.ValDef

abstract def valDef(sym: Universe.Symbol, rhs: Universe.Tree): Universe.ValDef

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any

final def ##(): Int

Definition Classes
AnyRef → Any

def +(other: String): String

Implicit
This member is added by an implicit conversion from Universe.InternalApi to any2stringadd[Universe.InternalApi] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd

def ->[B](y: B): (Universe.InternalApi, B)

Implicit
This member is added by an implicit conversion from Universe.InternalApi to ArrowAssoc[Universe.InternalApi] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
@inline()

final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any

final def asInstanceOf[T0]: T0

Definition Classes
Any

def clone(): AnyRef

Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws( ... ) @native()

def ensuring(cond: (Universe.InternalApi) ⇒ Boolean, msg: ⇒ Any): Universe.InternalApi

Implicit
This member is added by an implicit conversion from Universe.InternalApi to Ensuring[Universe.InternalApi] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: (Universe.InternalApi) ⇒ Boolean): Universe.InternalApi

Implicit
This member is added by an implicit conversion from Universe.InternalApi to Ensuring[Universe.InternalApi] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean, msg: ⇒ Any): Universe.InternalApi

Implicit
This member is added by an implicit conversion from Universe.InternalApi to Ensuring[Universe.InternalApi] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean): Universe.InternalApi

Implicit
This member is added by an implicit conversion from Universe.InternalApi to Ensuring[Universe.InternalApi] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef

def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any

def finalize(): Unit

Attributes
protected[lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )

def formatted(fmtstr: String): String

Implicit
This member is added by an implicit conversion from Universe.InternalApi to StringFormat[Universe.InternalApi] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
@inline()

final def getClass(): Class[_]

Definition Classes
AnyRef → Any
Annotations
@native()

def hashCode(): Int

Definition Classes
AnyRef → Any
Annotations
@native()

final def isInstanceOf[T0]: Boolean

Definition Classes
Any

def manifestToTypeTag[T](mirror: Any, manifest: Manifest[T]): Universe.TypeTag[T]

Convert a scala.reflect.Manifest to a scala.reflect.api.TypeTags#TypeTag.

Compiler usually generates these conversions automatically, when a manifest for a type T is in scope, and an implicit of type TypeTag[T] is requested, but this method can also be called manually. For example:

manifestToTypeTag(scala.reflect.runtime.currentMirror, implicitly[Manifest[String]])

final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef

final def notify(): Unit

Definition Classes
AnyRef
Annotations
@native()

final def notifyAll(): Unit

Definition Classes
AnyRef
Annotations
@native()

final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef

def toString(): String

Definition Classes
AnyRef → Any

def typeTagToManifest[T](mirror: Any, tag: Universe.TypeTag[T])(implicit arg0: ClassTag[T]): Manifest[T]

Convert a scala.reflect.api.TypeTags#TypeTag to a scala.reflect.Manifest.

Compiler usually generates these conversions automatically, when a type tag for a type T is in scope, and an implicit of type Manifest[T] is requested, but this method can also be called manually. For example:

typeTagToManifest(scala.reflect.runtime.currentMirror, implicitly[TypeTag[String]])

final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )

final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )

final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... ) @native()

def →[B](y: B): (Universe.InternalApi, B)

Implicit
This member is added by an implicit conversion from Universe.InternalApi to ArrowAssoc[Universe.InternalApi] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc

© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.12.9/scala-reflect/scala/reflect/api/Internals$InternalApi.html