Class

scala.reflect.macros

Attachments

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abstract class Attachments extends AnyRef

EXPERIMENTAL

Attachments provide a way to associate custom metadata with symbols and trees.

Along with symbol and tpe, which represent core metadata of trees, each tree carries the attachments field that can store other metadata: compiler-defined (e.g. positions) or user-defined. Same story is true for symbols, which also have extensible metadata by the virtue of the same attachments field.

Typically attachments just store a scala.reflect.api.Position, but they can be extended to encompass arbitrary payloads. Payloads are stored in type-indexed slots, which can be read with get[T] and written with update[T] and remove[T].

This API doesn't have much use in the runtime reflection API (the scala.reflect.api package), but it might be of help for macro writers, providing a way to coordinate multiple macros operating on the same code. Therefore the attachments field is only declared in trees and symbols belonging to scala.reflect.macros.Universe.

Self Type
Attachments
Source
Attachments.scala
Linear Supertypes
Known Subclasses
Type Hierarchy
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  2. By Inheritance
Inherited
  1. Attachments
  2. AnyRef
  3. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
  2. All

Instance Constructors

  1. new Attachments()

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Type Members

  1. abstract type Pos >: Null

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    The position type of this attachment

Abstract Value Members

  1. abstract def pos: Pos

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    The underlying position

  2. abstract def withPos(newPos: Pos): Attachments { type Pos = Attachments.this.Pos }

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    Creates a copy of this attachment with the position replaced by newPos

Concrete Value Members

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

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    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

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    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

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

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

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    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).

    returns

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

    Definition Classes
    AnyRef → Any
  6. def all: Set[Any]

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    The underlying payload with the guarantee that no two elements have the same type.

  7. final def asInstanceOf[T0]: T0

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    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.

  8. def clone(): AnyRef

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    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

  9. def contains[T](implicit arg0: ClassTag[T]): Boolean

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    Check underlying payload contains an instance of type T.

  10. def ensuring(cond: (Attachments) ⇒ Boolean, msg: ⇒ Any): Attachments

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

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

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

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

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

    Tests whether the argument (that) 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
  15. def equals(arg0: Any): Boolean

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    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
  16. def finalize(): Unit

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    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

  17. def formatted(fmtstr: String): String

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    Implicit information
    This member is added by an implicit conversion from Attachments to StringFormat[Attachments] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  18. def get[T](implicit arg0: ClassTag[T]): Option[T]

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    An underlying payload of the given class type T.

  19. final def getClass(): Class[_]

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    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

  20. def hashCode(): Int

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    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
  21. def isEmpty: Boolean

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  22. final def isInstanceOf[T0]: Boolean

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    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
  23. final def ne(arg0: AnyRef): Boolean

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    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
  24. final def notify(): Unit

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    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

  25. final def notifyAll(): Unit

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    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

  26. def remove[T](implicit arg0: ClassTag[T]): Attachments { type Pos = Attachments.this.Pos }

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    Creates a copy of this attachment with the payload of the given class type T removed.

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

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    Definition Classes
    AnyRef
  28. def toString(): String

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    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
  29. def update[T](attachment: T)(implicit arg0: ClassTag[T]): Attachments { type Pos = Attachments.this.Pos }

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    Creates a copy of this attachment with the payload slot of T added/updated with the provided value.

    Creates a copy of this attachment with the payload slot of T added/updated with the provided value. Replaces an existing payload of the same type, if exists.

  30. final def wait(): Unit

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

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

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    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  33. def [B](y: B): (Attachments, B)

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

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from Attachments to any2stringadd[Attachments]

Inherited by implicit conversion StringFormat from Attachments to StringFormat[Attachments]

Inherited by implicit conversion Ensuring from Attachments to Ensuring[Attachments]

Inherited by implicit conversion ArrowAssoc from Attachments to ArrowAssoc[Attachments]

Ungrouped