Does this type conform to given type argument that
?
Is this type equivalent to given type argument that
?
This type as seen from prefix pre
and class clazz
. This means: Replace all ThisType
s of clazz
or one of its subclasses by pre
and instantiate all parameters by arguments of pre
. Proceed analogously for ThisType
s 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
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 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]
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.
Does this type contain a reference to given symbol?
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.
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.
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.
The erased type corresponding to this type after all transformations from Scala to Java have been performed.
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)))
Is there part of this type which satisfies predicate p
?
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
resultType
Returns optionally first type (in a preorder traversal) which satisfies predicate p
, or None if none exists.
Apply f
to each part of this type, for side effects only
Apply f
to each part of this type, returning a new type. children get mapped before their parents
The member with given name, either directly declared or inherited, an OverloadedSymbol if several exist, NoSymbol if none exist.
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.
Provides an alternate if type is NoType.
For a method or poly type, a list of its value parameter sections, the empty list of lists for all other types.
The result type of the method.
Substitute symbols 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.
Is this type a type constructor that is missing its type arguments?
The term symbol associated with the type, or NoSymbol
for types that do not refer to a term symbol.
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)
Returns the corresponding type constructor (e.g. List for List[T] or List[String])
For a poly type, its type parameters, the empty list for all other types.
The type symbol associated with the type, or NoSymbol
for types that do not refer to a type symbol.
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.
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.
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)))
(Since version 2.11.0) use dealias
or etaExpand
instead
(Since version 2.11.0) use paramLists
instead
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala-reflect/scala/reflect/api/Types$MethodTypeApi.html
The API that all method types support. The main source of information about types is the scala.reflect.api.Types page.