diff options
Diffstat (limited to 'src/library/scala/reflect/base/Types.scala')
| -rw-r--r-- | src/library/scala/reflect/base/Types.scala | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/src/library/scala/reflect/base/Types.scala b/src/library/scala/reflect/base/Types.scala index 839c49805a..b2ee3bc4d3 100644 --- a/src/library/scala/reflect/base/Types.scala +++ b/src/library/scala/reflect/base/Types.scala @@ -1,6 +1,14 @@ package scala.reflect package base +/** + * Defines the type hierachy for types. + * + * Note: Because of implementation details, some type factories have return type `Type` + * instead of a more precise type. + * + * @see [[scala.reflect]] for a description on how the class hierarchy is encoded here. + */ trait Types { self: Universe => /** The type of Scala types, and also Scala type signatures. @@ -26,14 +34,14 @@ trait Types { self: Universe => */ val NoPrefix: Type - /** The type of Scala singleton types, i.e. types that are inhabited + /** The type of Scala singleton types, i.e., types that are inhabited * by only one nun-null value. These include types of the forms * {{{ * C.this.type * C.super.type * x.type * }}} - * as well as constant types. + * as well as [[ConstantType constant types]]. */ type SingletonType >: Null <: Type @@ -42,8 +50,8 @@ trait Types { self: Universe => */ implicit val SingletonTypeTag: ClassTag[SingletonType] - /** The `ThisType` type describes types of the form on the left with the - * correspnding ThisType representations to the right. + /** A singleton type that describes types of the form on the left with the + * corresponding `ThisType` representation to the right: * {{{ * C.this.type ThisType(C) * }}} @@ -62,7 +70,10 @@ trait Types { self: Universe => * where `sym` is the class prefix of the this type. */ abstract class ThisTypeExtractor { - def apply(sym: Symbol): Type // not ThisTypebecause of implementation details + /** + * Creates a ThisType from the given class symbol. + */ + def apply(sym: Symbol): Type def unapply(tpe: ThisType): Option[Symbol] } @@ -120,7 +131,7 @@ trait Types { self: Universe => } /** The `ConstantType` type is not directly written in user programs, but arises as the type of a constant. - * The REPL expresses constant types like Int(11). Here are some constants with their types. + * The REPL expresses constant types like `Int(11)`. Here are some constants with their types: * {{{ * 1 ConstantType(Constant(1)) * "abc" ConstantType(Constant("abc")) @@ -401,7 +412,7 @@ trait Types { self: Universe => val WildcardType: Type /** BoundedWildcardTypes, used only during type inference, are created in - * two places that I can find: + * two places: * * 1. If the expected type of an expression is an existential type, * its hidden symbols are replaced with bounded wildcards. @@ -417,8 +428,12 @@ trait Types { self: Universe => */ implicit val BoundedWildcardTypeTag: ClassTag[BoundedWildcardType] + /** The constructor/deconstructor for `BoundedWildcardType` instances. */ val BoundedWildcardType: BoundedWildcardTypeExtractor + /** An extractor class to create and pattern match with syntax `BoundedWildcardTypeExtractor(bounds)` + * with `bounds` denoting the type bounds. + */ abstract class BoundedWildcardTypeExtractor { def apply(bounds: TypeBounds): BoundedWildcardType def unapply(tpe: BoundedWildcardType): Option[TypeBounds] |