scala.tools.nsc.transform.patmat

PatternMatching

trait PatternMatching extends SubComponent with Transform with TypingTransformers with Debugging with Interface with MatchTranslation with MatchTreeMaking with MatchCodeGen with MatchCps with ScalaLogic with Solving with MatchAnalysis with MatchOptimization with MatchWarnings

Translate pattern matching.

Either into optimized if/then/else's, or virtualized as method calls (these methods form a zero-plus monad), similar in spirit to how for-comprehensions are compiled.

For each case, express all patterns as extractor calls, guards as 0-ary extractors, and sequence them using flatMap (lifting the body of the case into the monad using one).

Cases are combined into a pattern match using the orElse combinator (the implicit failure case is expressed using the monad's zero).

TODO:

(longer-term) TODO:

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Inherited
  1. PatternMatching
  2. MatchWarnings
  3. MatchOptimization
  4. MatchAnalysis
  5. MatchApproximation
  6. Solving
  7. ScalaLogic
  8. TreeAndTypeAnalysis
  9. Logic
  10. MatchCps
  11. MatchTreeMaking
  12. MatchCodeGen
  13. MatchTranslation
  14. Interface
  15. TreeDSL
  16. Debugging
  17. TypingTransformers
  18. Transform
  19. SubComponent
  20. AnyRef
  21. Any
Implicitly
  1. by StringAdd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Type Members

  1. trait CNF extends PropositionalLogic

    Definition Classes
    Solving
  2. trait CheckableTreeAndTypeAnalysis extends AnyRef

    Definition Classes
    TreeAndTypeAnalysis
  3. trait CodegenCore extends MatchMonadInterface

    Definition Classes
    MatchCodeGen
  4. trait CommonSubconditionElimination extends OptimizedCodegen with MatchApproximator

    Definition Classes
    MatchOptimization
  5. trait MatchAnalyzer extends MatchApproximator

    Definition Classes
    MatchAnalysis
  6. trait MatchApproximator extends TreeMakers with TreesAndTypesDomain

    Represent a match as a formula in propositional logic that encodes whether the match matches (abstractly: we only consider types)

  7. trait MatchMonadInterface extends AnyRef

    Interface with user-defined match monad? if there's a __match in scope, we use this as the match strategy, assuming it conforms to MatchStrategy as defined below:

  8. trait MatchOptimizer extends OptimizedCodegen with SwitchEmission with CommonSubconditionElimination

    Definition Classes
    MatchOptimization
  9. class MatchTransformer extends TypingTransformer

  10. trait MatchTranslator extends PatternMatching.TreeMakers with PatternMatching.TreeMakerWarnings

    Definition Classes
    MatchTranslation
  11. trait OptimizedCodegen extends CodegenCore with TypedSubstitution with MatchMonadInterface

    Definition Classes
    MatchCodeGen
  12. class OptimizingMatchTranslator extends MatchTranslator with MatchOptimizer with MatchAnalyzer with Solver

  13. class Phase extends StdPhase

    The phase defined by this transform

  14. trait PropositionalLogic extends AnyRef

    Definition Classes
    Logic
  15. trait PureCodegen extends CodegenCore with PureMatchMonadInterface

    Definition Classes
    MatchCodeGen
  16. trait PureMatchMonadInterface extends MatchMonadInterface

    Definition Classes
    MatchCodeGen
  17. class PureMatchTranslator extends MatchTranslator with PureCodegen

  18. trait Solver extends CNF

    Definition Classes
    Solving
  19. abstract class StdPhase extends GlobalPhase

    A standard phase template

  20. final case class Suppression(exhaustive: Boolean, unreachable: Boolean) extends Product with Serializable

    Definition Classes
    MatchTreeMaking
  21. trait SwitchEmission extends TreeMakers with MatchMonadInterface

    Definition Classes
    MatchOptimization
  22. trait TreeMakerWarnings extends AnyRef

    Definition Classes
    MatchWarnings
  23. trait TreeMakers extends TypedSubstitution with CodegenCore

    Definition Classes
    MatchTreeMaking
  24. trait TreesAndTypesDomain extends PropositionalLogic with CheckableTreeAndTypeAnalysis

    Definition Classes
    ScalaLogic
  25. trait TypedSubstitution extends MatchMonadInterface

    Definition Classes
    Interface
  26. abstract class TypingTransformer extends Global.Transformer

    Definition Classes
    TypingTransformers

Abstract Value Members

  1. abstract val global: Global

    Definition Classes
    TreeDSL
  2. abstract val runsAfter: List[String]

    List of phase names, this phase should run after

    List of phase names, this phase should run after

    Definition Classes
    SubComponent
  3. abstract val runsRightAfter: Option[String]

    Phase name this phase will attach itself to, not allowing any phase to come between it and the phase name declared

    Phase name this phase will attach itself to, not allowing any phase to come between it and the phase name declared

    Definition Classes
    SubComponent

Concrete Value Members

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

    Definition Classes
    AnyRef
  2. final def !=(arg0: Any): Boolean

    Definition Classes
    Any
  3. final def ##(): Int

    Definition Classes
    AnyRef → Any
  4. def +(other: String): String

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

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

    Definition Classes
    AnyRef
  7. final def ==(arg0: Any): Boolean

    Definition Classes
    Any
  8. object CODE

    Definition Classes
    TreeDSL
  9. object Suppression extends Serializable

    Definition Classes
    MatchTreeMaking
  10. final def afterOwnPhase[T](op: ⇒ T): T

    Definition Classes
    SubComponent
    Annotations
    @inline()
  11. def alignAcrossRows(xss: List[List[AnyRef]], sep: String, lineSep: String = "\n"): String

    Definition Classes
    Logic
  12. final def asInstanceOf[T0]: T0

    Definition Classes
    Any
  13. final def beforeOwnPhase[T](op: ⇒ T): T

    Definition Classes
    SubComponent
    Annotations
    @inline()
  14. def clone(): AnyRef

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  15. final def dealiasWiden(tp: Global.Type): Global.Type

    Attributes
    protected
    Definition Classes
    Interface
  16. object debug

    Definition Classes
    Debugging
  17. def ensuring(cond: (PatternMatching) ⇒ Boolean, msg: ⇒ Any): PatternMatching

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

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

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

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

    Definition Classes
    AnyRef
  22. def equals(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any
  23. def finalize(): Unit

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  24. def formatted(fmtstr: String): String

    Implicit information
    This member is added by an implicit conversion from PatternMatching to StringFormat[PatternMatching] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  25. final def getClass(): Class[_]

    Definition Classes
    AnyRef → Any
  26. final def hasStableSymbol(p: Global.Tree): Boolean

    Attributes
    protected
    Definition Classes
    Interface
  27. def hashCode(): Int

    SubComponent are added to a HashSet and two phases are the same if they have the same name

    SubComponent are added to a HashSet and two phases are the same if they have the same name

    Definition Classes
    SubComponent → AnyRef → Any
  28. def instanceOfTpImplies(tp: Global.Type, tpImplied: Global.Type): Boolean

    Definition Classes
    TreeAndTypeAnalysis
  29. val internal: Boolean

    Internal flag to tell external from internal phases

    Internal flag to tell external from internal phases

    Definition Classes
    SubComponent
  30. final def isInstanceOf[T0]: Boolean

    Definition Classes
    Any
  31. final def mkFALSE: Global.Literal

    Attributes
    protected
    Definition Classes
    Interface
  32. final def mkTRUE: Global.Literal

    Attributes
    protected
    Definition Classes
    Interface
  33. final def ne(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef
  34. def newPhase(prev: nsc.Phase): StdPhase

    Create a new phase which applies transformer

    Create a new phase which applies transformer

    Definition Classes
    TransformSubComponent
  35. def newTransformer(unit: Global.CompilationUnit): Global.Transformer

    The transformer factory

    The transformer factory

    Definition Classes
    PatternMatchingTransform
  36. final def notify(): Unit

    Definition Classes
    AnyRef
  37. final def notifyAll(): Unit

    Definition Classes
    AnyRef
  38. def ownPhase: nsc.Phase

    The phase corresponding to this subcomponent in the current compiler run

    The phase corresponding to this subcomponent in the current compiler run

    Definition Classes
    SubComponent
  39. val phaseName: String

    The name of the phase

    The name of the phase

    Definition Classes
    PatternMatchingSubComponent
  40. def phaseNewFlags: Long

    New flags defined by the phase which are not valid before

    New flags defined by the phase which are not valid before

    Definition Classes
    SubComponent
  41. def phaseNextFlags: Long

    New flags defined by the phase which are not valid until immediately after it

    New flags defined by the phase which are not valid until immediately after it

    Definition Classes
    SubComponent
  42. def removeCPSFromPt(pt: Global.Type): Global.Type

    Definition Classes
    MatchCps
  43. val runsBefore: List[String]

    List of phase names, this phase should run before

    List of phase names, this phase should run before

    Definition Classes
    SubComponent
  44. def sameValue(a: Global.Tree, b: Global.Tree): Boolean

    Definition Classes
    TreeAndTypeAnalysis
  45. final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
    AnyRef
  46. def toString(): String

    Definition Classes
    AnyRef → Any
  47. object vpmName

    Definition Classes
    Interface
  48. final def wait(): Unit

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

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

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

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

Inherited from MatchWarnings

Inherited from MatchOptimization

Inherited from MatchAnalysis

Inherited from MatchApproximation

Inherited from Solving

Inherited from ScalaLogic

Inherited from TreeAndTypeAnalysis

Inherited from Logic

Inherited from MatchCps

Inherited from MatchTreeMaking

Inherited from MatchCodeGen

Inherited from MatchTranslation

Inherited from Interface

Inherited from TreeDSL

Inherited from Debugging

Inherited from TypingTransformers

Inherited from Transform

Inherited from SubComponent

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion StringAdd from PatternMatching to StringAdd[PatternMatching]

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

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

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

Ungrouped