scala3-compiler-bootstrapped
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Copyright (c) 2002-2023, LAMP/EPFL
scala3-compiler-bootstrapped/dotty.tools/dotty.tools.dotc/dotty.tools.dotc.transform/LambdaLift

LambdaLift

dotty.tools.dotc.transform.LambdaLift
See theLambdaLift companion object
class LambdaLift extends MiniPhase, IdentityDenotTransformer

This phase performs the necessary rewritings to eliminate classes and methods nested in other methods. In detail:

  1. It adds all free variables of local functions as additional parameters (proxies).
  2. It rebinds references to free variables to the corresponding proxies,
  3. It lifts all local functions and classes out as far as possible, but at least to the enclosing class.
  4. It stores free variables of non-trait classes as additional fields of the class. The fields serve as proxies for methods in the class, which avoids the need of passing additional parameters to these methods.

A particularly tricky case are local traits. These cannot store free variables as field proxies, because LambdaLift runs after Mixin, so the fields cannot be expanded anymore. Instead, methods of local traits get free variables of the trait as additional proxy parameters. The difference between local classes and local traits is illustrated by the two rewritings below.

def f(x: Int) = { def f(x: Int) = new C(x).f2 class C { ==> class C(x$1: Int) { def f2 = x def f2 = x$1 } } new C().f2 }

def f(x: Int) = { def f(x: Int) = new C().f2(x) trait T { ==> trait T def f2 = x def f2(x$1: Int) = x$1 } } class C extends T class C extends T new C().f2 }

Attributes

Companion
object
Graph
Supertypes
class MiniPhase
class Phase
class Object
trait Matchable
class Any
Show all
Self type

Members list

Value members

Concrete methods

override def description: String

Attributes

Definition Classes
override def initContext(ctx: FreshContext): Unit

Attributes

Definition Classes
override def phaseName: String

A name given to the Phase that can be used to debug the compiler. For instance, it is possible to print trees after a given phase using:

A name given to the Phase that can be used to debug the compiler. For instance, it is possible to print trees after a given phase using:

$ ./bin/scalac -Xprint:<phaseNameHere> sourceFile.scala

Attributes

Definition Classes
override def prepareForUnit(tree: Tree)(using Context): Context

Attributes

Definition Classes
override def relaxedTypingInGroup: Boolean

If set, use relaxed typing for all phases in group

If set, use relaxed typing for all phases in group

Attributes

Definition Classes
override def runsAfterGroupsOf: Set[String]

List of names of phases that should have finished their processing of all compilation units before this phase starts

List of names of phases that should have finished their processing of all compilation units before this phase starts

Attributes

Definition Classes
override def transformApply(tree: Apply)(using Context): Apply

Attributes

Definition Classes
override def transformClosure(tree: Closure)(using Context): Closure

Attributes

Definition Classes
override def transformDefDef(tree: DefDef)(using Context): Tree

Attributes

Definition Classes
override def transformIdent(tree: Ident)(using Context): Tree

Attributes

Definition Classes
override def transformReturn(tree: Return)(using Context): Tree

Attributes

Definition Classes
override def transformSelect(tree: Select)(using Context): Tree

Attributes

Definition Classes
override def transformTemplate(tree: Template)(using Context): Template

Attributes

Definition Classes
override def transformTypeDef(tree: TypeDef)(using Context): Tree

Attributes

Definition Classes

Inherited methods

final def <=(that: Phase): Boolean

Attributes

Inherited from:
Phase
def allowsImplicitSearch: Boolean

If set, implicit search is enabled

If set, implicit search is enabled

Attributes

Inherited from:
Phase
def changesBaseTypes: Boolean

Can this transform change the base types of a type?

Can this transform change the base types of a type?

Attributes

Inherited from:
Phase
def changesMembers: Boolean

Can this transform create or delete non-private members?

Can this transform create or delete non-private members?

Attributes

Inherited from:
Phase
def changesParents: Boolean

Can this transform change the parents of a class?

Can this transform change the parents of a class?

Attributes

Inherited from:
Phase
def checkPostCondition(tree: Tree)(using Context): Unit

Check what the phase achieves, to be called at any point after it is finished.

Check what the phase achieves, to be called at any point after it is finished.

Attributes

Inherited from:
Phase
def end: PhaseId

Attributes

Inherited from:
Phase
final def erasedTypes: Boolean

Attributes

Inherited from:
Phase
def exists: Boolean

Attributes

Inherited from:
Phase
final def flatClasses: Boolean

Attributes

Inherited from:
Phase
final def hasNext: Boolean

Attributes

Inherited from:
Phase
def id: Int

The sequence position of this phase in the given context where 0 is reserved for NoPhase and the first real phase is at position 1. -1 if the phase is not installed in the context.

The sequence position of this phase in the given context where 0 is reserved for NoPhase and the first real phase is at position 1. -1 if the phase is not installed in the context.

Attributes

Inherited from:
Phase
def isCheckable: Boolean

Output should be checkable by TreeChecker

Output should be checkable by TreeChecker

Attributes

Inherited from:
Phase
def isEnabled(using Context): Boolean

Attributes

Inherited from:
Phase
def isRunnable(using Context): Boolean

Attributes

Inherited from:
Phase
def isTyper: Boolean

Is this phase the standard typerphase? True for TyperPhase, but not for other first phases (such as FromTasty or Parser). The predicate is tested in some places that perform checks and corrections. It's different from ctx.isAfterTyper (and cheaper to test).

Is this phase the standard typerphase? True for TyperPhase, but not for other first phases (such as FromTasty or Parser). The predicate is tested in some places that perform checks and corrections. It's different from ctx.isAfterTyper (and cheaper to test).

Attributes

Inherited from:
Phase
final def iterator: Iterator[Phase]

Attributes

Inherited from:
Phase
final def lambdaLifted: Boolean

Attributes

Inherited from:
Phase
def lastPhaseId(using Context): Int

The last phase during which the transformed denotations are valid

The last phase during which the transformed denotations are valid

Attributes

Inherited from:
DenotTransformer
final def megaPhase(using Context): Phase

Attributes

Inherited from:
Phase
final def monitor(doing: String)(body: => Unit)(using Context): Unit

Attributes

Inherited from:
Phase
final def next: Phase

Attributes

Inherited from:
Phase
final def patternTranslated: Boolean

Attributes

Inherited from:
Phase
def period: Period

Attributes

Inherited from:
Phase
def prepareForAlternative(tree: Alternative)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForApply(tree: Apply)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForAssign(tree: Assign)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForBind(tree: Bind)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForBlock(tree: Block)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForCaseDef(tree: CaseDef)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForClosure(tree: Closure)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForDefDef(tree: DefDef)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForIdent(tree: Ident)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForIf(tree: If)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForInlined(tree: Inlined)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForLabeled(tree: Labeled)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForLiteral(tree: Literal)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForMatch(tree: Match)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForNew(tree: New)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForOther(tree: Tree)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForPackageDef(tree: PackageDef)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForQuote(tree: Quote)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForReturn(tree: Return)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForSelect(tree: Select)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForSeqLiteral(tree: SeqLiteral)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForSplice(tree: Splice)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForStats(trees: List[Tree])(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForSuper(tree: Super)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTemplate(tree: Template)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForThis(tree: This)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTry(tree: Try)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTypeApply(tree: TypeApply)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTypeDef(tree: TypeDef)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTypeTree(tree: TypeTree)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForTyped(tree: Typed)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForUnApply(tree: UnApply)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForValDef(tree: ValDef)(using Context): Context

Attributes

Inherited from:
MiniPhase
def prepareForWhileDo(tree: WhileDo)(using Context): Context

Attributes

Inherited from:
MiniPhase
final def prev: Phase

Attributes

Inherited from:
Phase
final def refChecked: Boolean

Attributes

Inherited from:
Phase
final override def relaxedTyping: Boolean

If set, allow missing or superfluous arguments in applications and type applications.

If set, allow missing or superfluous arguments in applications and type applications.

Attributes

Definition Classes
Inherited from:
MiniPhase
override def run(using Context): Unit

Attributes

Definition Classes
Inherited from:
MiniPhase
def runOn(units: List[CompilationUnit])(using runCtx: Context): List[CompilationUnit]

Attributes

Inherited from:
Phase
def runsAfter: Set[String]

List of names of phases that should precede this phase

List of names of phases that should precede this phase

Attributes

Inherited from:
Phase
final def sameBaseTypesStartId: Int

Attributes

Inherited from:
Phase
final def sameMembersStartId: Int

Attributes

Inherited from:
Phase
final def sameParentsStartId: Int

Attributes

Inherited from:
Phase
def show(tree: Tree)(using Context): String

Convert a compilation unit's tree to a string; can be overridden

Convert a compilation unit's tree to a string; can be overridden

Attributes

Inherited from:
Phase
protected def singletonGroup: MegaPhase

Attributes

Inherited from:
MiniPhase
def start: Int

Attributes

Inherited from:
Phase
override def toString: String

Returns a string representation of the object.

Returns a string representation of the object.

The default representation is platform dependent.

Attributes

Returns

a string representation of the object.

Definition Classes
Phase -> Any
Inherited from:
Phase
def transform(ref: SingleDenotation)(using Context): SingleDenotation

The transformation method

The transformation method

Attributes

Inherited from:
IdentityDenotTransformer
def transformAllDeep(tree: Tree)(using Context): Tree

Transform tree using all transforms of current group (including this one)

Transform tree using all transforms of current group (including this one)

Attributes

Inherited from:
MiniPhase
def transformAlternative(tree: Alternative)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformAssign(tree: Assign)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformBind(tree: Bind)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformBlock(tree: Block)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformCaseDef(tree: CaseDef)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformFollowing(tree: Tree)(using Context): Tree

Transform single node using all transforms following the current one in this group

Transform single node using all transforms following the current one in this group

Attributes

Inherited from:
MiniPhase
def transformFollowingDeep(tree: Tree)(using Context): Tree

Transform tree using all transforms following the current one in this group

Transform tree using all transforms following the current one in this group

Attributes

Inherited from:
MiniPhase
def transformIf(tree: If)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformInlined(tree: Inlined)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformLabeled(tree: Labeled)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformLiteral(tree: Literal)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformMatch(tree: Match)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformNew(tree: New)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformOther(tree: Tree)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformPackageDef(tree: PackageDef)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformQuote(tree: Quote)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformSeqLiteral(tree: SeqLiteral)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformSplice(tree: Splice)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformStats(trees: List[Tree])(using Context): List[Tree]

Attributes

Inherited from:
MiniPhase
def transformSuper(tree: Super)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformThis(tree: This)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformTry(tree: Try)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformTypeApply(tree: TypeApply)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformTypeTree(tree: TypeTree)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformTyped(tree: Typed)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformUnApply(tree: UnApply)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformUnit(tree: Tree)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformValDef(tree: ValDef)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def transformWhileDo(tree: WhileDo)(using Context): Tree

Attributes

Inherited from:
MiniPhase
def validFor(using Context): Period

The validity period of the transformed denotations in the given context

The validity period of the transformed denotations in the given context

Attributes

Inherited from:
DenotTransformer

Inherited fields

val cpy: TypedTreeCopier

Attributes

Inherited from:
MiniPhase
Generated with
Copyright (c) 2002-2023, LAMP/EPFL
Copyright (c) 2002-2023, LAMP/EPFL