scala.reflect.api.Types

TypeBoundsApi

Related Doc: package Types

trait TypeBoundsApi extends Universe.TypeApi

The API that all type bounds support. The main source of information about types is the scala.reflect.api.Types page.

Self Type
Universe.TypeBounds
Source
Types.scala
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TypeBounds
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Abstract Value Members

  1. abstract def <:<(that: Universe.Type): Boolean

    Does this type conform to given type argument that?

    Does this type conform to given type argument that?

    Definition Classes
    TypeApi
  2. abstract def =:=(that: Universe.Type): Boolean

    Is this type equivalent to given type argument that?

    Is this type equivalent to given type argument that?

    Definition Classes
    TypeApi
  3. abstract def asSeenFrom(pre: Universe.Type, clazz: Universe.Symbol): Universe.Type

    This type as seen from prefix pre and class clazz.

    This type as seen from prefix pre and class clazz. This means: Replace all ThisTypes of clazz or one of its subclasses by pre and instantiate all parameters by arguments of pre. Proceed analogously for ThisTypes referring to outer classes.

    Example:

    scala> import scala.reflect.runtime.universe._
    import scala.reflect.runtime.universe._
    
    scala> class D[T] { def m: T = ??? }
    defined class D
    
    scala> class C extends D[Int]
    defined class C
    
    scala> val D = typeOf[D[_]].typeSymbol.asClass
    D: reflect.runtime.universe.ClassSymbol = class D
    
    scala> val C = typeOf[C].typeSymbol.asClass
    C: reflect.runtime.universe.ClassSymbol = class C
    
    scala> val T = D.typeParams(0).asType.toType
    T: reflect.runtime.universe.Type = T
    
    scala> T.asSeenFrom(ThisType(C), D)
    res0: reflect.runtime.universe.Type = scala.Int
    Definition Classes
    TypeApi
  4. abstract def baseClasses: List[Universe.Symbol]

    The list of all base classes of this type (including its own typeSymbol) in linearization order, starting with the class itself and ending in class Any.

    The list of all base classes of this type (including its own typeSymbol) in linearization order, starting with the class itself and ending in class Any.

    Definition Classes
    TypeApi
  5. abstract def baseType(clazz: Universe.Symbol): Universe.Type

    The least type instance of given class which is a super-type of this type.

    The least type instance of given class which is a super-type of this type. Example:

    class D[T]
    class C extends p.D[Int]
    ThisType(C).baseType(D) = p.D[Int]
    Definition Classes
    TypeApi
  6. abstract def companion: Universe.Type

    Type signature of the companion of the underlying class symbol.

    Type signature of the companion of the underlying class symbol. NoType if the underlying symbol is not a class symbol, or if it doesn't have a companion.

    Definition Classes
    TypeApi
  7. abstract def contains(sym: Universe.Symbol): Boolean

    Does this type contain a reference to given symbol?

    Does this type contain a reference to given symbol?

    Definition Classes
    TypeApi
  8. abstract def dealias: Universe.Type

    Expands type aliases arising from type members.

    Expands type aliases arising from type members. Note that type aliases can hide beneath singleton types and singleton types can hide inside type aliases. Moreover, aliases might lurk in the upper bounds of abstract types. Therefore careful thought has to be applied to identify and carry out unwrapping logic specific to your use case.

    Definition Classes
    TypeApi
  9. abstract def decl(name: Universe.Name): Universe.Symbol

    The defined or declared members with name name in this type; an OverloadedSymbol if several exist, NoSymbol if none exist.

    The defined or declared members with name name in this type; an OverloadedSymbol if several exist, NoSymbol if none exist. Alternatives of overloaded symbol appear in the order they are declared.

    Definition Classes
    TypeApi
  10. abstract def decls: Universe.MemberScope

    A Scope containing directly declared members of this type.

    A Scope containing directly declared members of this type. Unlike members this method doesn't returns inherited members.

    Members in the returned scope might appear in arbitrary order. Use declarations.sorted to get an ordered list of members.

    Definition Classes
    TypeApi
  11. abstract def erasure: Universe.Type

    The erased type corresponding to this type after all transformations from Scala to Java have been performed.

    The erased type corresponding to this type after all transformations from Scala to Java have been performed.

    Definition Classes
    TypeApi
  12. abstract def etaExpand: Universe.Type

    Converts higher-kinded TypeRefs to PolyTypes.

    Converts higher-kinded TypeRefs to PolyTypes. Functions on types are also implemented as PolyTypes.

    Example: (in the below, <List> is the type constructor of List) TypeRef(pre, <List>, List()) is replaced by PolyType(X, TypeRef(pre, <List>, List(X)))

    Definition Classes
    TypeApi
  13. abstract def exists(p: (Universe.Type) ⇒ Boolean): Boolean

    Is there part of this type which satisfies predicate p?

    Is there part of this type which satisfies predicate p?

    Definition Classes
    TypeApi
  14. abstract def finalResultType: Universe.Type

    For a curried/nullary method or poly type its non-method result type, the type itself for all other types.

    For a curried/nullary method or poly type its non-method result type, the type itself for all other types.

    scala> class C {
         | def foo[T](x: T)(y: T) = ???
         | def bar: Int = ???
         | }
    defined class C
    
    scala> typeOf[C].member(TermName("foo")).asMethod
    res0: reflect.runtime.universe.MethodSymbol = method foo
    
    scala> res0.info // PolyType wrapping a MethodType
    res1: reflect.runtime.universe.Type = [T](x: T)(y: T)scala.Nothing
    
    scala> res1.resultType // MethodType wrapping a MethodType
    res2: reflect.runtime.universe.Type = (x: T)(y: T)scala.Nothing
    
    scala> res1.resultType.resultType // vanilla MethodType
    res3: reflect.runtime.universe.Type = (y: T)scala.Nothing
    
    scala> res1.resultType.resultType.resultType
    res4: reflect.runtime.universe.Type = scala.Nothing
    
    scala> res1.finalResultType
    res5: reflect.runtime.universe.Type = scala.Nothing
    
    scala> typeOf[C].member(TermName("bar")).asMethod
    res6: reflect.runtime.universe.MethodSymbol = method bar
    
    scala> res6.info
    res7: reflect.runtime.universe.Type = => scala.Int
    
    scala> res6.info.resultType
    res8: reflect.runtime.universe.Type = scala.Int
    
    scala> res6.info.finalResultType
    res9: reflect.runtime.universe.Type = scala.Int
    Definition Classes
    TypeApi
    See also

    resultType

  15. abstract def find(p: (Universe.Type) ⇒ Boolean): Option[Universe.Type]

    Returns optionally first type (in a preorder traversal) which satisfies predicate p, or None if none exists.

    Returns optionally first type (in a preorder traversal) which satisfies predicate p, or None if none exists.

    Definition Classes
    TypeApi
  16. abstract def foreach(f: (Universe.Type) ⇒ Unit): Unit

    Apply f to each part of this type, for side effects only

    Apply f to each part of this type, for side effects only

    Definition Classes
    TypeApi
  17. abstract def hi: Universe.Type

    The upper bound.

    The upper bound. Is equal to definitions.AnyTpe if not specified explicitly.

  18. abstract def lo: Universe.Type

    The lower bound.

    The lower bound. Is equal to definitions.NothingTpe if not specified explicitly.

  19. abstract def map(f: (Universe.Type) ⇒ Universe.Type): Universe.Type

    Apply f to each part of this type, returning a new type.

    Apply f to each part of this type, returning a new type. children get mapped before their parents

    Definition Classes
    TypeApi
  20. abstract def member(name: Universe.Name): Universe.Symbol

    The member with given name, either directly declared or inherited, an OverloadedSymbol if several exist, NoSymbol if none exist.

    The member with given name, either directly declared or inherited, an OverloadedSymbol if several exist, NoSymbol if none exist.

    Definition Classes
    TypeApi
  21. abstract def members: Universe.MemberScope

    A Scope containing all members of this type (directly declared or inherited).

    A Scope containing all members of this type (directly declared or inherited). Unlike declarations this method also returns inherited members.

    Members in the returned scope might appear in arbitrary order. Use declarations.sorted to get an ordered list of members.

    Definition Classes
    TypeApi
  22. abstract def orElse(alt: ⇒ Universe.Type): Universe.Type

    Provides an alternate if type is NoType.

    Provides an alternate if type is NoType.

    Definition Classes
    TypeApi
  23. abstract def paramLists: List[List[Universe.Symbol]]

    For a method or poly type, a list of its value parameter sections, the empty list of lists for all other types.

    For a method or poly type, a list of its value parameter sections, the empty list of lists for all other types.

    Definition Classes
    TypeApi
  24. abstract def resultType: Universe.Type

    For a (nullary) method or poly type, its direct result type (can be a MethodType if the method has multiple argument lists), the type itself for all other types.

    For a (nullary) method or poly type, its direct result type (can be a MethodType if the method has multiple argument lists), the type itself for all other types.

    scala> class C { def foo[T](x: T)(y: T) = ??? }
    defined class C
    
    scala> typeOf[C].member(TermName("foo")).asMethod
    res0: reflect.runtime.universe.MethodSymbol = method foo
    
    scala> res0.info // PolyType wrapping a MethodType
    res1: reflect.runtime.universe.Type = [T](x: T)(y: T)scala.Nothing
    
    scala> res1.resultType // MethodType wrapping a MethodType
    res2: reflect.runtime.universe.Type = (x: T)(y: T)scala.Nothing
    
    scala> res1.resultType.resultType // vanilla MethodType
    res3: reflect.runtime.universe.Type = (y: T)scala.Nothing
    
    scala> res1.resultType.resultType.resultType
    res4: reflect.runtime.universe.Type = scala.Nothing
    
    scala> res1.finalResultType
    res5: reflect.runtime.universe.Type = scala.Nothing
    Definition Classes
    TypeApi
    See also

    finalResultType

  25. abstract def substituteSymbols(from: List[Universe.Symbol], to: List[Universe.Symbol]): Universe.Type

    Substitute symbols in to for corresponding occurrences of references to symbols from in this type.

    Substitute symbols in to for corresponding occurrences of references to symbols from in this type.

    Definition Classes
    TypeApi
  26. abstract def substituteTypes(from: List[Universe.Symbol], to: List[Universe.Type]): Universe.Type

    Substitute types in to for corresponding occurrences of references to symbols from in this type.

    Substitute types in to for corresponding occurrences of references to symbols from in this type.

    Definition Classes
    TypeApi
  27. abstract def takesTypeArgs: Boolean

    Is this type a type constructor that is missing its type arguments?

    Is this type a type constructor that is missing its type arguments?

    Definition Classes
    TypeApi
  28. abstract def termSymbol: Universe.Symbol

    The term symbol associated with the type, or NoSymbol for types that do not refer to a term symbol.

    The term symbol associated with the type, or NoSymbol for types that do not refer to a term symbol.

    Definition Classes
    TypeApi
  29. abstract def typeArgs: List[Universe.Type]

    List of type arguments ingrained in this type reference.

    List of type arguments ingrained in this type reference. Depending on your use case you might or might not want to call dealias first.

    scala> type T = List[Int]
    defined type alias T
    
    scala> typeOf[T].typeArgs
    res0: List[reflect.runtime.universe.Type] = List()
    
    scala> typeOf[T].dealias.typeArgs
    res1: List[reflect.runtime.universe.Type] = List(scala.Int)
    Definition Classes
    TypeApi
  30. abstract def typeConstructor: Universe.Type

    Returns the corresponding type constructor (e.g.

    Returns the corresponding type constructor (e.g. List for List[T] or List[String])

    Definition Classes
    TypeApi
  31. abstract def typeParams: List[Universe.Symbol]

    For a poly type, its type parameters, the empty list for all other types.

    For a poly type, its type parameters, the empty list for all other types.

    Definition Classes
    TypeApi
  32. abstract def typeSymbol: Universe.Symbol

    The type symbol associated with the type, or NoSymbol for types that do not refer to a type symbol.

    The type symbol associated with the type, or NoSymbol for types that do not refer to a type symbol.

    Definition Classes
    TypeApi
  33. abstract def weak_<:<(that: Universe.Type): Boolean

    Does this type weakly conform to given type argument that, i.e., either conforms in terms of <:< or both are primitive number types that conform according to Section "Weak Conformance" in the spec.

    Does this type weakly conform to given type argument that, i.e., either conforms in terms of <:< or both are primitive number types that conform according to Section "Weak Conformance" in the spec. For example, Int weak_<:< Long.

    Definition Classes
    TypeApi
  34. abstract def widen: Universe.Type

    If this is a singleton type, widen it to its nearest underlying non-singleton base type by applying one or more underlying dereferences.

    If this is a singleton type, widen it to its nearest underlying non-singleton base type by applying one or more underlying dereferences. If this is not a singleton type, returns this type itself.

    Example:

    class Outer { class C ; val x: C } val o: Outer <o.x.type>.widen = o.C

    Note that type aliases can hide beneath singleton types and singleton types can hide inside type aliases. Moreover, aliases might lurk in the upper bounds of abstract types. Therefore careful thought has to be applied to identify and carry out unwrapping logic specific to your use case.

    Definition Classes
    TypeApi
  35. abstract def declaration(name: Universe.Name): Universe.Symbol

    Definition Classes
    TypeApi
    Annotations
    @deprecated
    Deprecated

    (Since version 2.11.0) Use decl instead

    See also

    decl

  36. abstract def declarations: Universe.MemberScope

    Definition Classes
    TypeApi
    Annotations
    @deprecated
    Deprecated

    (Since version 2.11.0) Use decls instead

    See also

    decls

  37. abstract def normalize: Universe.Type

    Reduce to beta eta-long normal form.

    Reduce to beta eta-long normal form. Expands type aliases and converts higher-kinded TypeRefs to PolyTypes. Functions on types are also implemented as PolyTypes.

    Example: (in the below, <List> is the type constructor of List) TypeRef(pre, <List>, List()) is replaced by PolyType(X, TypeRef(pre, <List>, List(X)))

    Definition Classes
    TypeApi
    Annotations
    @deprecated
    Deprecated

    (Since version 2.11.0) Use dealias or etaExpand instead

  38. abstract def paramss: List[List[Universe.Symbol]]

    Definition Classes
    TypeApi
    Annotations
    @deprecated
    Deprecated

    (Since version 2.11.0) Use paramLists instead

    See also

    paramLists

Concrete Value Members

  1. final def !=(arg0: Any): Boolean

    Test two objects for inequality.

    Test two objects for inequality.

    returns

    true if !(this == that), false otherwise.

    Definition Classes
    AnyRef → Any
  2. final def ##(): Int

    Equivalent to x.hashCode except for boxed numeric types and null.

    Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

    returns

    a hash value consistent with ==

    Definition Classes
    AnyRef → Any
  3. def +(other: String): String

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to any2stringadd[Universe.TypeBoundsApi] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (Universe.TypeBoundsApi, B)

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to ArrowAssoc[Universe.TypeBoundsApi] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    Definition Classes
    AnyRef → Any
  6. final def asInstanceOf[T0]: T0

    Cast the receiver object to be of type T0.

    Cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

    the receiver object.

    Definition Classes
    Any
    Exceptions thrown

    ClassCastException if the receiver object is not an instance of the erasure of type T0.

  7. def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object.

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

    not specified by SLS as a member of AnyRef

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

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to Ensuring[Universe.TypeBoundsApi] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  9. def ensuring(cond: (Universe.TypeBoundsApi) ⇒ Boolean): Universe.TypeBoundsApi

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to Ensuring[Universe.TypeBoundsApi] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  10. def ensuring(cond: Boolean, msg: ⇒ Any): Universe.TypeBoundsApi

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to Ensuring[Universe.TypeBoundsApi] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  11. def ensuring(cond: Boolean): Universe.TypeBoundsApi

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to Ensuring[Universe.TypeBoundsApi] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  12. final def eq(arg0: AnyRef): Boolean

    Tests whether the argument (arg0) is a reference to the receiver object (this).

    Tests whether the argument (arg0) is a reference to the receiver object (this).

    The eq method implements an equivalence relation on non-null instances of AnyRef, and has three additional properties:

    • It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false.
    • For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false.
    • null.eq(null) returns true.

    When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).

    returns

    true if the argument is a reference to the receiver object; false otherwise.

    Definition Classes
    AnyRef
  13. def equals(arg0: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to eq.

    See also equals in scala.Any.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    Definition Classes
    AnyRef → Any
  14. def finalize(): Unit

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the finalize method is invoked, as well as the interaction between finalize and non-local returns and exceptions, are all platform dependent.

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

    not specified by SLS as a member of AnyRef

  15. def formatted(fmtstr: String): String

    Implicit information
    This member is added by an implicit conversion from Universe.TypeBoundsApi to StringFormat[Universe.TypeBoundsApi] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  16. final def getClass(): Class[_]

    A representation that corresponds to the dynamic class of the receiver object.

    A representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

    a representation that corresponds to the dynamic class of the receiver object.

    Definition Classes
    AnyRef → Any
    Note

    not specified by SLS as a member of AnyRef

  17. def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

    the hash code value for this object.

    Definition Classes
    AnyRef → Any
  18. final def isInstanceOf[T0]: Boolean

    Test whether the dynamic type of the receiver object is T0.

    Test whether the dynamic type of the receiver object is T0.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    Definition Classes
    Any
  19. final def ne(arg0: AnyRef): Boolean

    Equivalent to !(this eq that).

    Equivalent to !(this eq that).

    returns

    true if the argument is not a reference to the receiver object; false otherwise.

    Definition Classes
    AnyRef
  20. final def notify(): Unit

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

  21. final def notifyAll(): Unit

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
    AnyRef
    Note

    not specified by SLS as a member of AnyRef

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

    Definition Classes
    AnyRef
  23. def toString(): String

    Creates a String representation of this object.

    Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

    returns

    a String representation of the object.

    Definition Classes
    AnyRef → Any
  24. final def wait(): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  25. final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  26. final def wait(arg0: Long): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  27. def [B](y: B): (Universe.TypeBoundsApi, B)

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

Inherited from Universe.TypeApi

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from Universe.TypeBoundsApi to any2stringadd[Universe.TypeBoundsApi]

Inherited by implicit conversion StringFormat from Universe.TypeBoundsApi to StringFormat[Universe.TypeBoundsApi]

Inherited by implicit conversion Ensuring from Universe.TypeBoundsApi to Ensuring[Universe.TypeBoundsApi]

Inherited by implicit conversion ArrowAssoc from Universe.TypeBoundsApi to ArrowAssoc[Universe.TypeBoundsApi]

Helpers

Ungrouped