Annotation scala.reflect.api.Trees.UnApply
Companion class UnApplyExtractor
abstract type UnApply >: Null <: Universe.UnApplyApi with Universe.TermTree
Abstract Value Members
abstract def args: List[Universe.Tree]
The arguments of the unapplication. See the example for scala.reflect.api.Trees#UnApplyExtractor.
- Definition Classes
- UnApplyApi
abstract def canEqual(that: Any): Boolean
- Definition Classes
- Equals
abstract def canHaveAttrs: Boolean
Can this tree carry attributes (i.e. symbols, types or positions)? Typically the answer is yes, except for the EmptyTree null object and two special singletons: noSelfType and pendingSuperCall.
- Definition Classes
- TreeApi
abstract def children: List[Universe.Tree]
The direct child trees of this tree. EmptyTrees are always omitted. Lists are flattened.
- Definition Classes
- TreeApi
abstract def collect[T](pf: PartialFunction[Universe.Tree, T]): List[T]
Apply pf to each subtree on which the function is defined and collect the results.
- Definition Classes
- TreeApi
abstract def duplicate: TreeApi.this.type
Make a copy of this tree, keeping all attributes, except that all positions are focused (so nothing in this tree will be found when searching by position).
- Definition Classes
- TreeApi
abstract def equalsStructure(that: Universe.Tree): Boolean
Tests whether two trees are structurally equal. Note that == on trees is reference equality.
- Definition Classes
- TreeApi
abstract def exists(p: (Universe.Tree) => Boolean): Boolean
Is there exists a part of this tree which satisfies predicate p?
- Definition Classes
- TreeApi
abstract def filter(f: (Universe.Tree) => Boolean): List[Universe.Tree]
Find all subtrees matching predicate p. Same as withFilter
- Definition Classes
- TreeApi
abstract def find(p: (Universe.Tree) => Boolean): Option[Universe.Tree]
Returns optionally first tree (in a preorder traversal) which satisfies predicate p, or None if none exists.
- Definition Classes
- TreeApi
abstract def forAll(p: (Universe.Tree) => Boolean): Boolean
Do all parts of this tree satisfy predicate p?
- Definition Classes
- TreeApi
abstract def foreach(f: (Universe.Tree) => Unit): Unit
Apply f to each subtree
- Definition Classes
- TreeApi
abstract def fun: Universe.Tree
A dummy node that carries the type of unapplication. See the example for scala.reflect.api.Trees#UnApplyExtractor.
- Definition Classes
- UnApplyApi
abstract def isDef: Boolean
Does this tree represent a definition? (of a method, of a class, etc)
- Definition Classes
- TreeApi
abstract def isEmpty: Boolean
Is this tree one of the empty trees?
Empty trees are: the EmptyTree null object and TypeTree instances that don't carry a type.
- Definition Classes
- TreeApi
- See also
canHaveAttrs
abstract def isTerm: Boolean
The canonical way to test if a Tree represents a term.
- Definition Classes
- TreeApi
abstract def isType: Boolean
The canonical way to test if a Tree represents a type.
- Definition Classes
- TreeApi
abstract def nonEmpty: Boolean
Is this tree not an empty tree?
- Definition Classes
- TreeApi
- See also
isEmpty
abstract def orElse(alt: => Universe.Tree): Universe.Tree
Provides an alternate if tree is empty
- alt
The alternate tree
- returns
If this tree is non empty, this tree, otherwise
alt.
- Definition Classes
- TreeApi
abstract def pos: Universe.Position
Position of the tree.
- Definition Classes
- TreeApi
abstract def productArity: Int
- Definition Classes
- Product
abstract def productElement(n: Int): Any
- Definition Classes
- Product
abstract def symbol: Universe.Symbol
Symbol of the tree.
For most trees symbol is null. In SymTrees, it is overridden and implemented with a var, initialized to NoSymbol.
Trees which are not SymTrees but which carry symbols do so by overriding def symbol to forward it elsewhere. Examples:
Super(qual, _) has qual's symbol,
Apply(fun, args) has fun's symbol,
TypeApply(fun, args) has fun's symbol,
AppliedTypeTree(tpt, args) has tpt's symbol,
TypeTree(tpe) has tpe's typeSymbol, if tpe != null. - Definition Classes
- TreeApi
abstract def tpe: Universe.Type
Type of the tree.
Upon creation most trees have their tpe set to null. Types are typically assigned to trees during typechecking. Some node factory methods set tpe immediately after creation.
When the typechecker encounters a tree with a non-null tpe, it will assume it to be correct and not check it again. This means one has to be careful not to erase the tpe field of subtrees.
- Definition Classes
- TreeApi
abstract def withFilter(f: (Universe.Tree) => Boolean): List[Universe.Tree]
Find all subtrees matching predicate p. Same as filter
- Definition Classes
- TreeApi
Concrete Value Members
final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
final def ##(): Int
- Definition Classes
- AnyRef → Any
final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
final def asInstanceOf[T0]: T0
- Definition Classes
- Any
def clone(): AnyRef
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
def finalize(): Unit
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
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()
def productElementName(n: Int): String
- Definition Classes
- Product
def productElementNames: Iterator[String]
- Definition Classes
- Product
def productIterator: Iterator[Any]
- Definition Classes
- Product
def productPrefix: String
- Definition Classes
- Product
final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
def toString(): String
Obtains string representation of a tree
- Definition Classes
- TreeApi → AnyRef → Any
final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()
© 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/Trees$UnApply.html
Used to represent
unapplymethods in pattern matching.For example:
2 match { case Foo(x) => x }Is represented as:
Match( Literal(Constant(2)), List( CaseDef( UnApply( // a dummy node that carries the type of unapplication to patmat // the <unapply-selector> here doesn't have an underlying symbol // it only has a type assigned, therefore after `untypecheck` this tree is no longer typeable Apply(Select(Ident(Foo), TermName("unapply")), List(Ident(TermName("<unapply-selector>")))), // arguments of the unapply => nothing synthetic here List(Bind(TermName("x"), Ident(nme.WILDCARD)))), EmptyTree, Ident(TermName("x")))))Introduced by typer. Eliminated by compiler phases patmat (in the new pattern matcher of 2.10) or explicitouter (in the old pre-2.10 pattern matcher).