trait MatchTranslator extends PatternMatching.TreeMakers with PatternMatching.TreeMakerWarnings
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- class Substitution extends AnyRef
- Definition Classes
- TypedSubstitution
- trait AbsCodegen extends AnyRef
- Definition Classes
- CodegenCore
- trait Casegen extends AbsCodegen
- Definition Classes
- CodegenCore
- abstract class CommonCodegen extends AbsCodegen
- Definition Classes
- CodegenCore
- final case class BoundTree(binder: Global.Symbol, tree: Global.Tree) extends Product with Serializable
- abstract class ExtractorCall extends PatternMatching.ExtractorAlignment
- class ExtractorCallProd extends ExtractorCall
- class ExtractorCallRegular extends ExtractorCall
- final case class TranslationStep(makers: List[MatchTranslator.TreeMaker], subpatterns: List[BoundTree]) extends Product with Serializable
- case class AlternativesTreeMaker(prevBinder: Global.Symbol, altss: List[List[TreeMaker]], pos: Global.Position) extends TreeMaker with NoNewBinders with Product with Serializable
- Definition Classes
- TreeMakers
- case class BodyTreeMaker(body: Global.Tree, matchPt: Global.Type) extends TreeMaker with NoNewBinders with Product with Serializable
- Definition Classes
- TreeMakers
- sealed abstract class CondTreeMaker extends FunTreeMaker
- Definition Classes
- TreeMakers
- case class EqualityTestTreeMaker(prevBinder: Global.Symbol, patTree: Global.Tree, pos: Global.Position) extends CondTreeMaker with Product with Serializable
- Definition Classes
- TreeMakers
- case class ExtractorTreeMaker(extractor: Global.Tree, extraCond: Option[Global.Tree], nextBinder: Global.Symbol)(subPatBinders: List[Global.Symbol], subPatRefs: List[Global.Tree], potentiallyMutableBinders: Set[Global.Symbol], extractorReturnsBoolean: Boolean, checkedLength: Option[Int], prevBinder: Global.Symbol, ignoredSubPatBinders: Set[Global.Symbol]) extends FunTreeMaker with PreserveSubPatBinders with Product with Serializable
Make a TreeMaker that will result in an extractor call specified by
extractorthe next TreeMaker (here, we don't know which it'll be) is chained after this one by flatMap'ing a function with bindernextBinderover our extractor's result the function's body is determined by the next TreeMaker (furthermore, the interpretation offlatMapdepends on the codegen instance we're using).Make a TreeMaker that will result in an extractor call specified by
extractorthe next TreeMaker (here, we don't know which it'll be) is chained after this one by flatMap'ing a function with bindernextBinderover our extractor's result the function's body is determined by the next TreeMaker (furthermore, the interpretation offlatMapdepends on the codegen instance we're using).The values for the subpatterns, as computed by the extractor call in
extractor, are stored in local variables that re-use the symbols insubPatBinders. This makes extractor patterns more debuggable (scala/bug#5739).- Definition Classes
- TreeMakers
- sealed abstract class FunTreeMaker extends TreeMaker
- Definition Classes
- TreeMakers
- case class GuardTreeMaker(guardTree: Global.Tree) extends TreeMaker with NoNewBinders with Product with Serializable
- Definition Classes
- TreeMakers
- sealed trait NoNewBinders extends TreeMaker
- Definition Classes
- TreeMakers
- case class NonNullTestTreeMaker(prevBinder: Global.Symbol, expectedTp: Global.Type, pos: Global.Position) extends FunTreeMaker with Product with Serializable
Make a TreeMaker that performs null check.
Make a TreeMaker that performs null check. This is called prior to extractor call.
- Definition Classes
- TreeMakers
- sealed trait PreserveSubPatBinders extends TreeMaker
- Definition Classes
- TreeMakers
- case class ProductExtractorTreeMaker(prevBinder: Global.Symbol, extraCond: Option[Global.Tree])(subPatBinders: List[Global.Symbol], subPatRefs: List[Global.Tree], mutableBinders: List[Global.Symbol], ignoredSubPatBinders: Set[Global.Symbol]) extends FunTreeMaker with PreserveSubPatBinders with Product with Serializable
An optimized version of ExtractorTreeMaker for Products.
An optimized version of ExtractorTreeMaker for Products. For now, this is hard-coded to case classes, and we simply extract the case class fields.
The values for the subpatterns, as specified by the case class fields at the time of extraction, are stored in local variables that re-use the symbols in
subPatBinders. This makes extractor patterns more debuggable (scala/bug#5739) as well as avoiding mutation after the pattern has been matched (scala/bug#5158, scala/bug#6070)TODO: make this user-definable as follows When a companion object defines a method
def unapply_1(x: T): U_1, but nodef unapplyordef unapplySeq, the extractor is considered to match any non-null value of type T the pattern is expected to have as many sub-patterns as there aredef unapply_I(x: T): U_Imethods, and the type of the I'th sub-pattern isU_I. The same exception for Seq patterns applies: if the last extractor is of typeSeq[U_N], the pattern must have at least N arguments (exactly N if the last argument is annotated with: _*). The arguments starting at N (and beyond) are taken from the sequence returned by apply_N, and it is checked that that sequence has enough elements to provide values for all expected sub-patterns.For a case class C, the implementation is assumed to be
def unapply_I(x: C) = x._I, and the extractor call is inlined under that assumption.- Definition Classes
- TreeMakers
- case class SubstOnlyTreeMaker(prevBinder: Global.Symbol, nextBinder: Global.Symbol) extends TreeMaker with Product with Serializable
- Definition Classes
- TreeMakers
- abstract class TreeMaker extends AnyRef
- Definition Classes
- TreeMakers
- case class TrivialTreeMaker(tree: Global.Tree) extends TreeMaker with NoNewBinders with Product with Serializable
- Definition Classes
- TreeMakers
- case class TypeTestTreeMaker(prevBinder: Global.Symbol, testedBinder: Global.Symbol, expectedTp: Global.Type, nextBinderTp: Global.Type)(pos: Global.Position, extractorArgTypeTest: Boolean = false) extends CondTreeMaker with Product with Serializable
implements the run-time aspects of (§8.2) (typedPattern has already done the necessary type transformations)
implements the run-time aspects of (§8.2) (typedPattern has already done the necessary type transformations)
Type patterns consist of types, type variables, and wildcards. A type pattern T is of one of the following forms:
- A reference to a class C, p.C, or T#C. This type pattern matches any non-null instance of the given class. Note that the prefix of the class, if it is given, is relevant for determining class instances. For instance, the pattern p.C matches only instances of classes C which were created with the path p as prefix. The bottom types scala.Nothing and scala.Null cannot be used as type patterns, because they would match nothing in any case.
- A singleton type p.type. This type pattern matches only the value denoted by the path p (that is, a pattern match involved a comparison of the matched value with p using method eq in class AnyRef). // TODO: the actual pattern matcher uses ==, so that's what I'm using for now // https://github.com/scala/bug/issues/4577 "pattern matcher, still disappointing us at equality time"
- A compound type pattern T1 with ... with Tn where each Ti is a type pat- tern. This type pattern matches all values that are matched by each of the type patterns Ti.
- A parameterized type pattern T[a1,...,an], where the ai are type variable patterns or wildcards _. This type pattern matches all values which match T for some arbitrary instantiation of the type variables and wildcards. The bounds or alias type of these type variable are determined as described in (§8.3).
- A parameterized type pattern scala.Array[T1], where T1 is a type pattern. // TODO This type pattern matches any non-null instance of type scala.Array[U1], where U1 is a type matched by T1.
- Definition Classes
- TreeMakers
Abstract Value Members
- abstract def analyzeCases(prevBinder: Global.Symbol, cases: List[List[TreeMaker]], pt: Global.Type, suppression: PatternMatching.Suppression): Unit
- Definition Classes
- TreeMakers
- abstract def codegen: AbsCodegen
- Definition Classes
- CodegenCore
- abstract def optimizeCases(prevBinder: Global.Symbol, cases: List[List[TreeMaker]], pt: Global.Type, selectorPos: Global.Position): (List[List[TreeMaker]], List[Global.Tree])
- Definition Classes
- TreeMakers
- abstract def selectorPos: Global.Position
- abstract val typer: (analyzer)#Typer
- Definition Classes
- MatchMonadInterface
Concrete Value Members
- object EmptySubstitution extends Substitution
- Definition Classes
- TypedSubstitution
- object Substitution
- Definition Classes
- TypedSubstitution
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##: Int
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toany2stringadd[PatternMatching.MatchTranslator] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
- def ->[B](y: B): (PatternMatching.MatchTranslator, B)
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toArrowAssoc[PatternMatching.MatchTranslator] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def checkMatchVariablePatterns(cases: List[Global.CaseDef]): Unit
- Definition Classes
- TreeMakerWarnings
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
- def combineCases(scrut: Global.Tree, scrutSym: Global.Symbol, cases: List[List[TreeMaker]], pt: Global.Type, selectorPos: Global.Position, owner: Global.Symbol, matchFailGenOverride: Option[(Global.Tree) => Global.Tree], suppression: PatternMatching.Suppression): Global.Tree
- Definition Classes
- TreeMakers
- def combineExtractors(treeMakers: List[TreeMaker])(casegen: Casegen): Global.Tree
- Definition Classes
- TreeMakers
- val debugInfoEmitVars: Boolean
- Attributes
- protected
- Definition Classes
- TreeMakers
- def emitSwitch(scrut: Global.Tree, scrutSym: Global.Symbol, cases: List[List[TreeMaker]], pt: Global.Type, matchFailGenOverride: Option[(Global.Tree) => Global.Tree], unchecked: Boolean): Option[Global.Tree]
- Definition Classes
- TreeMakers
- def emitTypeSwitch(bindersAndCases: List[(Global.Symbol, List[TreeMaker])], pt: Global.Type): Option[List[Global.CaseDef]]
- Definition Classes
- TreeMakers
- def ensuring(cond: (PatternMatching.MatchTranslator) => Boolean, msg: => Any): PatternMatching.MatchTranslator
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toEnsuring[PatternMatching.MatchTranslator] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: (PatternMatching.MatchTranslator) => Boolean): PatternMatching.MatchTranslator
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toEnsuring[PatternMatching.MatchTranslator] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean, msg: => Any): PatternMatching.MatchTranslator
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toEnsuring[PatternMatching.MatchTranslator] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean): PatternMatching.MatchTranslator
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toEnsuring[PatternMatching.MatchTranslator] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- def fixerUpper(origOwner: Global.Symbol, pos: Global.Position): Global.InternalTraverser
- Attributes
- protected
- Definition Classes
- TreeMakers
- def freshName(prefix: String): Global.TermName
- Definition Classes
- CodegenCore
- def freshSym(pos: Global.Position, tp: Global.Type = NoType, prefix: String = "x"): Global.TermSymbol
- Definition Classes
- CodegenCore
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- def getSuppression(scrut: Global.Tree): PatternMatching.Suppression
- Definition Classes
- TreeMakers
- def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- val matchOwner: Global.Symbol
- Definition Classes
- MatchMonadInterface
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def newSynthCaseLabel(name: String): Global.MethodSymbol
- Definition Classes
- CodegenCore
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- def propagateSubstitution(treeMakers: List[TreeMaker], initial: Substitution): List[TreeMaker]
- Definition Classes
- TreeMakers
- def removeSubstOnly(makers: List[TreeMaker]): collection.immutable.List[TreeMaker]
- Definition Classes
- TreeMakers
- def reportMissingCases(pos: Global.Position, counterExamples: List[String]): Unit
- Definition Classes
- MatchMonadInterface
- def reportUnreachable(pos: Global.Position): Unit
- Definition Classes
- MatchMonadInterface
- def requiresSwitch(scrut: Global.Tree, cases: List[List[TreeMaker]]): Boolean
- Definition Classes
- TreeMakers
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- AnyRef → Any
- def translateBody(body: Global.Tree, matchPt: Global.Type): TreeMaker
- def translateCase(scrutSym: Global.Symbol, pt: Global.Type)(caseDef: Global.CaseDef): List[TreeMaker]
The translation of
pat if guard => bodyhas two aspects: 1) the substitution due to the variables bound by patterns 2) the combination of the extractor calls usingflatMap.The translation of
pat if guard => bodyhas two aspects: 1) the substitution due to the variables bound by patterns 2) the combination of the extractor calls usingflatMap.2) is easy -- it looks like:
translatePattern_1.flatMap(translatePattern_2....flatMap(translatePattern_N.flatMap(translateGuard.flatMap((x_i) => success(Xbody(x_i)))))...)this must be right-leaning tree, as can be seen intuitively by considering the scope of bound variables: variables bound by pat_1 must be visible from the function inside the left-most flatMap right up to Xbody all the way on the right 1) is tricky because translatePattern_i determines the shape of translatePattern_i+1: zoom in ontranslatePattern_1.flatMap(translatePattern_2)for example -- it actually looks more like:translatePattern_1(x_scrut).flatMap((x_1) => {y_i -> x_1._i}translatePattern_2)x_1references the result (inside the monad) of the extractor corresponding topat_1, this result holds the values for the constructor arguments, which translatePattern_1 has extracted from the object pointed to byx_scrut. They_iare the symbols bound bypat_1(in order) in the scope of the remainder of the pattern, and they must thus be replaced by:- (for 1-ary unapply) x_1
- (for n-ary unapply, n > 1) selection of the i'th tuple component of
x_1 - (for unapplySeq) x_1.apply(i)
in the treemakers,
Thus, the result type of
translatePattern_i's extractor must conform toM[(T_1,..., T_n)].Operationally, phase 1) is a foldLeft, since we must consider the depth-first-flattening of the transformed patterns from left to right. For every pattern ast node, it produces a transformed ast and a function that will take care of binding and substitution of the next ast (to the right).
- def translateGuard(guard: Global.Tree): List[TreeMaker]
- def translateMatch(match_: Global.Match): Global.Tree
NOTE: the resulting tree is not type checked, nor are nested pattern matches transformed thus, you must typecheck the result (and that will in turn translate nested matches) this could probably be optimized...
- def translatePattern(bound: BoundTree): List[TreeMaker]
- def translateTry(caseDefs: List[Global.CaseDef], pt: Global.Type, pos: Global.Position): List[Global.CaseDef]
- def unreachableTypeSwitchCase(cases: List[Global.CaseDef]): Option[Global.CaseDef]
- Definition Classes
- TreeMakers
- 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()
- object ExtractorCall
- object PatternBoundToUnderscore
- object SymbolBound
- object WildcardPattern
A conservative approximation of which patterns do not discern anything.
A conservative approximation of which patterns do not discern anything. They are discarded during the translation.
- object TypeTestTreeMaker extends java.io.Serializable
- Definition Classes
- TreeMakers
Deprecated Value Members
- def formatted(fmtstr: String): String
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toStringFormat[PatternMatching.MatchTranslator] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.12.16) Use
formatString.format(value)instead ofvalue.formatted(formatString), or use thef""string interpolator. In Java 15 and later,formattedresolves to the new method in String which has reversed parameters.
- def →[B](y: B): (PatternMatching.MatchTranslator, B)
- Implicit
- This member is added by an implicit conversion from PatternMatching.MatchTranslator toArrowAssoc[PatternMatching.MatchTranslator] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
->instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.
The Scala compiler and reflection APIs.