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:

Linear Supertypes
MatchWarnings, MatchOptimization, MatchAnalysis, MatchApproximation, Solving, ScalaLogic, TreeAndTypeAnalysis, Logic, MatchCps, MatchTreeMaking, MatchCodeGen, MatchTranslation, Interface, TreeDSL, Debugging, TypingTransformers, Transform, SubComponent, AnyRef, Any
Known Subclasses
patmat
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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]

    Names of phases that must run before this phase.

    Names of phases that must run before this phase.

    Definition Classes
    SubComponent

  3. abstract val runsRightAfter: Option[String]

    Name of the phase that this phase must follow immediately.

    Name of the phase that this phase must follow immediately.

    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 enabled: Boolean

    Is this component enabled? Default is true.

    Is this component enabled? Default is true.

    Definition Classes
    SubComponent

  18. 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

  19. 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

  20. 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

  21. 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

  22. final def eq(arg0: AnyRef): Boolean

    Definition Classes
    AnyRef

  23. def equals(arg0: Any): Boolean

    Definition Classes
    AnyRef → Any

  24. def finalize(): Unit

    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )

  25. 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()

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

    Definition Classes
    AnyRef → Any

  27. final def hasStableSymbol(p: Global.Tree): Boolean

    Attributes
    protected
    Definition Classes
    Interface

  28. 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

  29. val initial: Boolean

    True if this phase runs before all other phases.

    True if this phase runs before all other phases. Usually, parser.

    Definition Classes
    SubComponent

  30. def instanceOfTpImplies(tp: Global.Type, tpImplied: Global.Type): Boolean

    Definition Classes
    TreeAndTypeAnalysis

  31. val internal: Boolean

    True if this phase is not provided by a plug-in.

    True if this phase is not provided by a plug-in.

    Definition Classes
    SubComponent

  32. final def isInstanceOf[T0]: Boolean

    Definition Classes
    Any

  33. final def mkFALSE: Global.Literal

    Attributes
    protected
    Definition Classes
    Interface

  34. final def mkTRUE: Global.Literal

    Attributes
    protected
    Definition Classes
    Interface

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

    Definition Classes
    AnyRef

  36. def newPhase(prev: nsc.Phase): StdPhase

    Create a new phase which applies transformer

    Create a new phase which applies transformer

    Definition Classes
    Transform → SubComponent

  37. def newTransformer(unit: Global.CompilationUnit): Global.Transformer

    The transformer factory

    The transformer factory

    Definition Classes
    PatternMatching → Transform

  38. final def notify(): Unit

    Definition Classes
    AnyRef

  39. final def notifyAll(): Unit

    Definition Classes
    AnyRef

  40. 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

  41. val phaseName: String

    The name of the phase

    The name of the phase

    Definition Classes
    PatternMatching → SubComponent

  42. 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

  43. 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

  44. def removeCPSFromPt(pt: Global.Type): Global.Type

    Definition Classes
    MatchCps

  45. val requires: List[String]

    Names of phases required by this component.

    Names of phases required by this component. Default is Nil.

    Definition Classes
    SubComponent

  46. val runsBefore: List[String]

    Names of phases that must run after this phase.

    Names of phases that must run after this phase. Default is Nil.

    Definition Classes
    SubComponent

  47. def sameValue(a: Global.Tree, b: Global.Tree): Boolean

    Definition Classes
    TreeAndTypeAnalysis

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

    Definition Classes
    AnyRef

  49. val terminal: Boolean

    True if this phase runs after all other phases.

    True if this phase runs after all other phases. Usually, terminal.

    Definition Classes
    SubComponent

  50. def toString(): String

    Definition Classes
    AnyRef → Any

  51. object vpmName

    Definition Classes
    Interface

  52. final def wait(): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )

  53. final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )

  54. final def wait(arg0: Long): Unit

    Definition Classes
    AnyRef
    Annotations
    @throws( ... )

  55. 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