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/Scala 2.13 Reflection

Object scala.reflect.runtime.JavaUniverse.treeInfo

object treeInfo extends TreeInfo

Definition Classes
JavaUniverse → SymbolTable
Source
JavaUniverse.scala
Linear Supertypes
TreeInfo, AnyRef, Any

Type Members

class Applied extends AnyRef

Applications in Scala can have one of the following shapes:

1) naked core: Ident(_) or Select(_, _) or basically anything else 2) naked core with targs: TypeApply(core, targs) or AppliedTypeTree(core, targs) 3) apply or several applies wrapping a core: Apply(core, _), or Apply(Apply(core, _), _), etc

This class provides different ways to decompose applications and simplifies their analysis.

***Examples*** (TypeApply in the examples can be replaced with AppliedTypeTree)

Ident(foo): * callee = Ident(foo) * core = Ident(foo) * targs = Nil * argss = Nil

TypeApply(foo, List(targ1, targ2...)) * callee = TypeApply(foo, List(targ1, targ2...)) * core = foo * targs = List(targ1, targ2...) * argss = Nil

Apply(foo, List(arg1, arg2...)) * callee = foo * core = foo * targs = Nil * argss = List(List(arg1, arg2...))

Apply(Apply(foo, List(arg21, arg22, ...)), List(arg11, arg12...)) * callee = foo * core = foo * targs = Nil * argss = List(List(arg11, arg12...), List(arg21, arg22, ...))

Apply(Apply(TypeApply(foo, List(targs1, targs2, ...)), List(arg21, arg22, ...)), List(arg11, arg12...)) * callee = TypeApply(foo, List(targs1, targs2, ...)) * core = foo * targs = Nil * argss = List(List(arg11, arg12...), List(arg21, arg22, ...))

Definition Classes
TreeInfo

class DynamicApplicationExtractor extends AnyRef

Definition Classes
TreeInfo

abstract class SeeThroughBlocks[T] extends AnyRef

Some handy extractors for spotting trees through the the haze of irrelevant braces: i.e. Block(Nil, SomeTree) should not keep us from seeing SomeTree.

Definition Classes
TreeInfo

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 val SYNTH_CASE_FLAGS: Long(2099200L)

Definition Classes
TreeInfo

def admitsTypeSelection(tree: JavaUniverse.Tree): Boolean

Is tree either a non-volatile type, or a path that does not include any of:

    a reference to a mutable variable/fielda reference to a by-name parametera member selection on a volatile type (Spec: 3.6 Volatile Types)?

Such a tree is a suitable target for type selection.

Definition Classes
TreeInfo

final def asInstanceOf[T0]: T0

Definition Classes
Any

def assignmentToMaybeNamedArg(tree: JavaUniverse.Tree): JavaUniverse.Tree

Translates an Assign(_, _) node to NamedArg(_, _) if the lhs is a simple ident. Otherwise returns unchanged.

Definition Classes
TreeInfo

def catchesThrowable(cdef: JavaUniverse.CaseDef): Boolean

Does this CaseDef catch Throwable?

Definition Classes
TreeInfo

def clone(): AnyRef

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

def dissectApplied(tree: JavaUniverse.Tree): Applied

Returns a wrapper that knows how to destructure and analyze applications.

Definition Classes
TreeInfo

def effectivePatternArity(args: List[JavaUniverse.Tree]): Int

//------------------------ => effectivePatternArity(args)
case Extractor(a)          => 1
case Extractor(a, b)       => 2
case Extractor((a, b))     => 2
case Extractor(a @ (b, c)) => 2
Definition Classes
TreeInfo

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])

def firstConstructor(stats: List[JavaUniverse.Tree]): JavaUniverse.Tree

The first constructor definitions in stats

Definition Classes
TreeInfo

def firstConstructorArgs(stats: List[JavaUniverse.Tree]): List[JavaUniverse.Tree]

The arguments to the first constructor in stats.

Definition Classes
TreeInfo

final def firstDefinesClassOrObject(trees: List[JavaUniverse.Tree], name: JavaUniverse.Name): Boolean

Does list of trees start with a definition of a class or module with given name (ignoring imports)

Definition Classes
TreeInfo
Annotations
@tailrec()

def flattenedPatternArgs(args: List[JavaUniverse.Tree]): List[JavaUniverse.Tree]

Definition Classes
TreeInfo

def foreachMethodParamAndArg(params: List[JavaUniverse.Symbol], args: List[JavaUniverse.Tree])(f: (JavaUniverse.Symbol, JavaUniverse.Tree) => Unit): Boolean

Definition Classes
TreeInfo

final def getClass(): Class[_ <: AnyRef]

Definition Classes
AnyRef → Any
Annotations
@native()

val global: JavaUniverse.this.type

Definition Classes
treeInfo → TreeInfo

def hasSynthCaseSymbol(t: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def hasUntypedPreSuperFields(stats: List[JavaUniverse.Tree]): Boolean

Definition Classes
TreeInfo

def hasVolatileType(tree: JavaUniverse.Tree): Boolean

Is tree's type volatile? (Ignored if its symbol has the @uncheckedStable annotation.)

Definition Classes
TreeInfo

def hashCode(): Int

Definition Classes
AnyRef → Any
Annotations
@native()

def isAbsTypeDef(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isAliasTypeDef(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isApplyDynamicName(name: JavaUniverse.Name): Boolean

Definition Classes
TreeInfo

def isByNameParamType(tpt: JavaUniverse.Tree): Boolean

Is tpt a by-name parameter type of the form => T?

Definition Classes
TreeInfo

def isCatchCase(cdef: JavaUniverse.CaseDef): Boolean

Is this pattern node a catch-all or type-test pattern?

Definition Classes
TreeInfo

def isConstructorWithDefault(t: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isDeclarationOrTypeDef(tree: JavaUniverse.Tree): Boolean

Is tree a declaration or type definition?

Definition Classes
TreeInfo

def isDefaultCase(cdef: JavaUniverse.CaseDef): Boolean

Is this pattern node a catch-all (wildcard or variable) pattern?

Definition Classes
TreeInfo

def isDefaultGetter(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isEarlyDef(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isEarlyValDef(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

final def isExprSafeToInline(tree: JavaUniverse.Tree): Boolean

Is tree an expression which can be inlined without affecting program semantics?

Note that this is not called "isExprPure" since purity (lack of side-effects) is not the litmus test. References to modules and lazy vals are side-effecting, both because side-effecting code may be executed and because the first reference takes a different code path than all to follow; but they are safe to inline because the expression result from evaluating them is always the same.

Definition Classes
TreeInfo
Annotations
@tailrec()

def isFunctionMissingParamType(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isGuardedCase(cdef: JavaUniverse.CaseDef): Boolean

Is this case guarded?

Definition Classes
TreeInfo

final def isInstanceOf[T0]: Boolean

Definition Classes
Any

def isInterfaceMember(tree: JavaUniverse.Tree): Boolean

Is tree legal as a member definition of an interface?

Definition Classes
TreeInfo

def isLiteralString(t: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isMacroApplication(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

final def isMacroApplicationOrBlock(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo
Annotations
@tailrec()

final def isNullaryInvocation(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo
Annotations
@tailrec()

def isPartialFunctionMissingParamType(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isPath(tree: JavaUniverse.Tree, allowVolatile: Boolean): Boolean

Is tree a path, defined as follows? (Spec: 3.1 Paths)

- The empty path ε (which cannot be written explicitly in user programs). - C.this, where C references a class. - p.x where p is a path and x is a stable member of p. - C.super.x or C.super[M].x where C references a class and x references a stable member of the super class or designated parent class M of C.

NOTE: Trees with errors are (mostly) excluded.

Path ::= StableId | [id ‘.’] this

Definition Classes
TreeInfo

def isPureDef(tree: JavaUniverse.Tree): Boolean

Is tree a pure (i.e. non-side-effecting) definition?

Definition Classes
TreeInfo

final def isPureExprForWarningPurposes(tree: JavaUniverse.Tree): Boolean

As if the name of the method didn't give it away, this logic is designed around issuing helpful warnings and minimizing spurious ones. That means don't reuse it for important matters like inlining decisions.

Definition Classes
TreeInfo
Annotations
@tailrec()

def isQualifierSafeToElide(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isRepeatedParamType(tpt: JavaUniverse.Tree): Boolean

Is tpt a vararg type of the form T* ?

Definition Classes
TreeInfo

def isSelfConstrCall(tree: JavaUniverse.Tree): Boolean

Is tree a self constructor call this(...)? I.e. a call to a constructor of the same object?

Definition Classes
TreeInfo

def isSelfOrSuperConstrCall(tree: JavaUniverse.Tree): Boolean

Is tree a self or super constructor call?

Definition Classes
TreeInfo

def isSequenceValued(tree: JavaUniverse.Tree): Boolean

Is this pattern node a sequence-valued pattern?

Definition Classes
TreeInfo

def isStableIdentifier(tree: JavaUniverse.Tree, allowVolatile: Boolean): Boolean

Is tree a stable identifier, a path which ends in an identifier?

StableId ::= id | Path ‘.’ id | [id ’.’] ‘super’ [‘[’ id ‘]’] ‘.’ id

Definition Classes
TreeInfo

def isStableIdentifierPattern(tree: JavaUniverse.Tree): Boolean

Is tree admissible as a stable identifier pattern (8.1.5 Stable Identifier Patterns)?

We disregard volatility, as it's irrelevant in patterns (scala/bug#6815)

Definition Classes
TreeInfo

def isStableMemberOf(sym: JavaUniverse.Symbol, tree: JavaUniverse.Tree, allowVolatile: Boolean): Boolean

Assuming sym is a member of tree, is it a "stable member"?

Stable members are packages or members introduced by object definitions or by value definitions of non-volatile types (§3.6).

Definition Classes
TreeInfo

def isStar(x: JavaUniverse.Tree): Boolean

Is this tree a Star(_) after removing bindings?

Definition Classes
TreeInfo

def isSuperConstrCall(tree: JavaUniverse.Tree): Boolean

Is tree a super constructor call?

Definition Classes
TreeInfo

def isSwitchAnnotation(tpe: JavaUniverse.Type): Boolean

a Match(Typed(_, tpt), _) must be translated into a switch if isSwitchAnnotation(tpt.tpe)

Definition Classes
TreeInfo

def isSynthCaseSymbol(sym: JavaUniverse.Symbol): Boolean

Definition Classes
TreeInfo

def isSyntheticCase(cdef: JavaUniverse.CaseDef): Boolean

Is this CaseDef synthetically generated, e.g. by MatchTranslation.translateTry?

Definition Classes
TreeInfo

def isSyntheticDefaultCase(cdef: JavaUniverse.CaseDef): Boolean

Is this pattern node a synthetic catch-all case, added during PartialFunction synthesis before we know whether the user provided cases are exhaustive.

Definition Classes
TreeInfo

def isTraitRef(tree: JavaUniverse.Tree): Boolean

Definition Classes
TreeInfo

def isVarPattern(pat: JavaUniverse.Tree): Boolean

Is tree a variable pattern?

Definition Classes
TreeInfo

def isVarPatternDeep(tree: JavaUniverse.Tree): Boolean

Does this tree represent an irrefutable pattern match in the position for { <tree> <- expr } based only on information at the parser phase? To qualify, there may be no subtree that will be interpreted as a Stable Identifier Pattern, nor any type tests, even on TupleN. See scala/bug#6968.

For instance:

(foo @ (bar @ _)) = 0

is a not a variable pattern; if only binds names.

The following are not variable patterns.

`bar`
Bar
(a, b)
_: T

If the pattern is a simple identifier, it is always a variable pattern. For example, the following introduce new bindings:

for { X <- xs } yield X
for { `backquoted` <- xs } yield `backquoted`

Note that this differs from a case clause:

object X
scrut match {
   case X =>  // case _ if scrut == X
}

Background: https://groups.google.com/d/msg/scala-internals/qwa_XOw_7Ks/IktkeTBYqg0J

Definition Classes
TreeInfo

def isVariableOrGetter(tree: JavaUniverse.Tree): Boolean

Is tree a mutable variable, or the getter of a mutable field?

Definition Classes
TreeInfo

def isWildcardArg(tree: JavaUniverse.Tree): Boolean

Is the argument a wildcard argument of the form _ or x @ _?

Definition Classes
TreeInfo

def isWildcardStarArg(tree: JavaUniverse.Tree): Boolean

Is this argument node of the form <expr> : _* ?

Definition Classes
TreeInfo

def isWildcardStarArgList(trees: List[JavaUniverse.Tree]): Boolean

Does this argument list end with an argument of the form <expr> : _* ?

Definition Classes
TreeInfo

def isWildcardStarType(tree: JavaUniverse.Tree): Boolean

Is the argument a wildcard star type of the form _*?

Definition Classes
TreeInfo

def mapMethodParamsAndArgs[R](params: List[JavaUniverse.Symbol], args: List[JavaUniverse.Tree])(f: (JavaUniverse.Symbol, JavaUniverse.Tree) => R): List[R]

Definition Classes
TreeInfo

final def mayBeTypePat(tree: JavaUniverse.Tree): Boolean

can this type be a type pattern

Definition Classes
TreeInfo

def mayBeVarGetter(sym: JavaUniverse.Symbol): Boolean

Is symbol potentially a getter of a variable?

Definition Classes
TreeInfo

final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef

def noFieldFor(vd: JavaUniverse.ValDef, owner: JavaUniverse.Symbol): Boolean

Definition Classes
TreeInfo

final def notify(): Unit

Definition Classes
AnyRef
Annotations
@native()

final def notifyAll(): Unit

Definition Classes
AnyRef
Annotations
@native()

def preSuperFields(stats: List[JavaUniverse.Tree]): List[JavaUniverse.ValDef]

The value definitions marked PRESUPER in this statement sequence

Definition Classes
TreeInfo

final def stripCast(tree: JavaUniverse.Tree): JavaUniverse.Tree

Strips layers of .asInstanceOf[T] / _.$asInstanceOf[T]() from an expression

Definition Classes
TreeInfo
Annotations
@tailrec()

def stripNamedApplyBlock(tree: JavaUniverse.Tree): JavaUniverse.Tree

Named arguments can transform a constructor call into a block, e.g. <init>(b = foo, a = bar) is transformed to { val x$1 = foo val x$2 = bar <init>(x$2, x$1) }

Definition Classes
TreeInfo

final def synchronized[T0](arg0: => T0): T0

Definition Classes
AnyRef

def toString(): String

Definition Classes
AnyRef → Any

def typeParameters(tree: JavaUniverse.Tree): List[JavaUniverse.TypeDef]

If this tree has type parameters, those. Otherwise Nil.

Definition Classes
TreeInfo

final def unbind(x: JavaUniverse.Tree): JavaUniverse.Tree

The underlying pattern ignoring any bindings

Definition Classes
TreeInfo
Annotations
@tailrec()

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 Applied

Destructures applications into important subparts described in Applied class, namely into: core, targs and argss (in the specified order).

Trees which are not applications are also accepted. Their callee and core will be equal to the input, while targs and argss will be Nil.

The provided extractors don't expose all the API of the Applied class. For advanced use, call dissectApplied explicitly and use its methods instead of pattern matching.

Definition Classes
TreeInfo

object DynamicApplication extends DynamicApplicationExtractor

Definition Classes
TreeInfo

object DynamicApplicationNamed extends DynamicApplicationExtractor

Definition Classes
TreeInfo

object DynamicUpdate extends DynamicApplicationExtractor

Definition Classes
TreeInfo

object IsFalse extends SeeThroughBlocks[Boolean]

Definition Classes
TreeInfo

object IsTrue extends SeeThroughBlocks[Boolean]

Definition Classes
TreeInfo

object MacroImplReference

Definition Classes
TreeInfo

object StripCast

Definition Classes
TreeInfo

object Unapplied

Locates the synthetic Apply node corresponding to an extractor's call to unapply (unwrapping nested Applies) and returns the fun part of that Apply.

Definition Classes
TreeInfo

object WildcardStarArg

Definition Classes
TreeInfo

© 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/runtime/JavaUniverse$treeInfo$.html