scala.reflect.reify

# Phases

#### trait Phases extends Reshape with Calculate with Metalevels with Reify

Self Type
  Reifier
Source
  Phases.scala

Linear Supertypes
Reify, GenUtils, GenPositions, GenAnnotationInfos, GenTrees, GenNames, GenTypes, GenSymbols, Metalevels, Calculate, Reshape, AnyRef, Any
Known Subclasses
ApplyReifier, Reifier, Reifier, UnapplyReifier
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Inherited

1. Phases
2. Reify
3. GenUtils
4. GenPositions
5. GenAnnotationInfos
6. GenTrees
7. GenNames
8. GenTypes
9. GenSymbols
10. Metalevels
11. Calculate
12. Reshape
13. AnyRef
14. Any

Implicitly

1. by any2stringadd
2. by StringFormat
3. by Ensuring
4. by ArrowAssoc

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### Type Members

1. #### case class Reification(name: tools.nsc.Global.Name, binding: tools.nsc.Global.Tree, tree: tools.nsc.Global.Tree) extends Product with Serializable

   Definition Classes
     GenSymbols

2. #### implicit class RichCalculateSymbol extends AnyRef

   Definition Classes
     Calculate

3. #### implicit class RichCalculateType extends AnyRef

   Definition Classes
     Calculate

### Value Members

1. #### final def !=(arg0: Any): Boolean

   Definition Classes
     AnyRef → Any

2. #### final def ##(): Int

   Definition Classes
     AnyRef → Any

3. #### def +(other: String): String

   Implicit information
     This member is added by an implicit conversion from Phases to any2stringadd[Phases] performed by method any2stringadd in scala.Predef.
   Definition Classes
     any2stringadd

4. #### def ->[B](y: B): (Phases, B)

   Implicit information
     This member is added by an implicit conversion from Phases to ArrowAssoc[Phases] performed by method ArrowAssoc in scala.Predef.
   Definition Classes
     ArrowAssoc
   Annotations
     @inline()

5. #### final def ==(arg0: Any): Boolean

   Definition Classes
     AnyRef → Any

6. #### object TypedOrAnnotated

   Definition Classes
     GenUtils

7. #### final def asInstanceOf[T0]: T0

   Definition Classes
     Any

8. #### def boundSymbolsInCallstack: List[tools.nsc.Global.Symbol]

   Definition Classes
     Reify

9. #### val calculate: tools.nsc.Global.Traverser { ... /* 2 definitions in type refinement */ }

   Merely traverses the reifiee and records symbols local to the reifee along with their metalevels.

   Merely traverses the reifiee and records symbols local to the reifee along with their metalevels.

   Definition Classes
     Calculate

10. #### def call(fname: String, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

11. #### def clone(): AnyRef

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

12. #### def current: Any

    Definition Classes
      Reify

13. #### def currents: List[Any]

    Definition Classes
      Reify

14. #### def ensuring(cond: (Phases) ⇒ Boolean, msg: ⇒ Any): Phases

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

15. #### def ensuring(cond: (Phases) ⇒ Boolean): Phases

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

16. #### def ensuring(cond: Boolean, msg: ⇒ Any): Phases

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

17. #### def ensuring(cond: Boolean): Phases

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

18. #### final def eq(arg0: AnyRef): Boolean

    Definition Classes
      AnyRef

19. #### def equals(arg0: Any): Boolean

    Definition Classes
      AnyRef → Any

20. #### def finalize(): Unit

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

21. #### def formatted(fmtstr: String): String

    Implicit information
      This member is added by an implicit conversion from Phases to StringFormat[Phases] performed by method StringFormat in scala.Predef.
    Definition Classes
      StringFormat
    Annotations
      @inline()

22. #### final def getClass(): Class[_]

    Definition Classes
      AnyRef → Any

23. #### def hashCode(): Int

    Definition Classes
      AnyRef → Any

24. #### def isCrossStageTypeBearer(tree: tools.nsc.Global.Tree): Boolean

    Definition Classes
      GenUtils

25. #### final def isInstanceOf[T0]: Boolean

    Definition Classes
      Any

26. #### def isSemiConcreteTypeMember(tpe: tools.nsc.Global.Type): Boolean

    Definition Classes
      GenUtils

27. #### val metalevels: tools.nsc.Global.Transformer { ... /* 4 definitions in type refinement */ }

    Makes sense of cross-stage bindings.

    Makes sense of cross-stage bindings.

    Analysis of cross-stage bindings becomes convenient if we introduce the notion of metalevels. Metalevel of a tree is a number that gets incremented every time you reify something and gets decremented when you splice something. Metalevel of a symbol is equal to the metalevel of its definition.

    Example 1. Consider the following snippet:

    reify { val x = 2 // metalevel of symbol x is 1, because it's declared inside reify val y = reify{x} // metalevel of symbol y is 1, because it's declared inside reify // metalevel of Ident(x) is 2, because it's inside two reifies y.splice // metalevel of Ident(y) is 0, because it's inside a designator of a splice }

    Cross-stage bindings are introduced when symbol.metalevel != curr_metalevel. Both bindings introduced in Example 1 are cross-stage.

    Depending on what side of the inequality is greater, the following situations might occur:

    1) symbol.metalevel < curr_metalevel. In this case reifier will generate a free variable that captures both the name of the symbol (to be compiled successfully) and its value (to be run successfully). For example, x in Example 1 will be reified as follows: Ident(newFreeVar("x", IntTpe, x))

    2) symbol.metalevel > curr_metalevel. This leads to a metalevel breach that violates intuitive perception of splicing. As defined in macro spec, splicing takes a tree and inserts it into another tree - as simple as that. However, how exactly do we do that in the case of y.splice? In this very scenario we can use dataflow analysis and inline it, but what if y were a var, and what if it were calculated randomly at runtime?

    This question has a genuinely simple answer. Sure, we cannot resolve such splices statically (i.e. during macro expansion of `reify`), but now we have runtime toolboxes, so noone stops us from picking up that reified tree and evaluating it at runtime (in fact, this is something that `Expr.splice` does transparently).

    This is akin to early vs late binding dilemma. The prior is faster, plus, the latter (implemented with reflection) might not work because of visibility issues or might be not available on all platforms. But the latter still has its uses, so I'm allowing metalevel breaches, but introducing the -Xlog-runtime-evals to log them.

    upd. We no longer do that. In case of a runaway `splice` inside a `reify`, one will get a static error. Why? Unfortunately, the cute idea of transparently converting between static and dynamic splices has failed. 1) Runtime eval that services dynamic splices requires scala-compiler.jar, which might not be on library classpath 2) Runtime eval incurs a severe performance penalty, so it'd better to be explicit about it

    As we can see, the only problem is the fact that lhs'es of `splice` can be code blocks that can capture variables from the outside. Code inside the lhs of an `splice` is not reified, while the code from the enclosing reify is.

    Hence some bindings become cross-stage, which is not bad per se (in fact, some cross-stage bindings have sane semantics, as in the example above). However this affects freevars, since they are delicate inter-dimensional beings that refer to both current and next planes of existence. When splicing tears the fabric of the reality apart, some freevars have to go single-dimensional to retain their sanity.

    Example 2. Consider the following snippet:

    reify { val x = 2 reify{x}.splice }

    Since the result of the inner reify is wrapped in a splice, it won't be reified together with the other parts of the outer reify, but will be inserted into that result verbatim.

    The inner reify produces an Expr[Int] that wraps Ident(freeVar("x", IntTpe, x)). However the freevar the reification points to will vanish when the compiler processes the outer reify. That's why we need to replace that freevar with a regular symbol that will point to reified x.

    Example 3. Consider the following fragment:

    reify { val x = 2 val y = reify{x} y.splice }

    In this case the inner reify doesn't appear next to splice, so it will be reified together with x. This means that no special processing is needed here.

    Example 4. Consider the following fragment:

    reify { val x = 2 { val y = 2 val z = reify{reify{x + y}} z.splice }.splice }

    The reasoning from Example 2 still holds here - we do need to inline the freevar that refers to x. However, we must not touch anything inside the splice'd block, because it's not getting reified.

    Definition Classes
      Metalevels

28. #### def mirrorBuildCall(name: tools.nsc.Global.TermName, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

29. #### def mirrorCall(name: tools.nsc.Global.TermName, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

30. #### def mirrorFactoryCall(prefix: tools.nsc.Global.TermName, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

31. #### def mirrorFactoryCall(value: Product, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

32. #### def mirrorMirrorCall(name: tools.nsc.Global.TermName, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

33. #### def mirrorMirrorSelect(name: tools.nsc.Global.TermName): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

34. #### def mirrorSelect(name: tools.nsc.Global.TermName): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

35. #### def mirrorSelect(name: String): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

36. #### def mkList(args: List[tools.nsc.Global.Tree]): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

37. #### def mkListMap(args: List[tools.nsc.Global.Tree]): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

38. #### lazy val mkReificationPipeline: (tools.nsc.Global.Tree) ⇒ tools.nsc.Global.Tree

39. #### final def ne(arg0: AnyRef): Boolean

    Definition Classes
      AnyRef

40. #### final def notify(): Unit

    Definition Classes
      AnyRef

41. #### final def notifyAll(): Unit

    Definition Classes
      AnyRef

42. #### def origin(sym: tools.nsc.Global.Symbol): String

    Definition Classes
      GenUtils

43. #### def path(fullname: String, mkName: (String) ⇒ tools.nsc.Global.Name): tools.nsc.Global.Tree

    An (unreified) path that refers to definition with given fully qualified name

    An (unreified) path that refers to definition with given fully qualified name

    mkName

      Creator for last portion of name (either TermName or TypeName)

    Definition Classes
      GenUtils

44. #### def reificationIsConcrete: Boolean

    Keeps track of whether this reification contains abstract type parameters

    Keeps track of whether this reification contains abstract type parameters

    Definition Classes
      GenTypes

45. #### def reify(reifee: Any): tools.nsc.Global.Tree

    Reifies any supported value.

    Reifies any supported value. For internal use only, use `reified` instead.

    Definition Classes
      Reify

46. #### def reifyAnnotationInfo(ann: tools.nsc.Global.AnnotationInfo): tools.nsc.Global.Tree

    Definition Classes
      GenAnnotationInfos

47. #### def reifyBuildCall(name: tools.nsc.Global.TermName, args: Any*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

48. #### def reifyFlags(flags: tools.nsc.Global.FlagSet): tools.nsc.Global.Tree

    Definition Classes
      GenTrees

49. #### def reifyFreeTerm(binding: tools.nsc.Global.Tree): tools.nsc.Global.Tree

    Definition Classes
      GenSymbols

50. #### def reifyFreeType(binding: tools.nsc.Global.Tree): tools.nsc.Global.Tree

    Definition Classes
      GenSymbols

51. #### def reifyList(xs: List[Any]): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

52. #### def reifyMirrorObject(x: Product): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

53. #### def reifyMirrorObject(name: String): tools.nsc.Global.Tree

    Reify a case object defined in Mirror

    Reify a case object defined in Mirror

    Definition Classes
      GenUtils

54. #### def reifyModifiers(m: tools.nsc.Global.Modifiers): tools.nsc.Global.Tree

    Definition Classes
      GenTrees

55. #### def reifyName(name: tools.nsc.Global.Name): tools.nsc.Global.Tree

    Definition Classes
      GenNames

56. #### def reifyPosition(pos: tools.nsc.Global.Position): tools.nsc.Global.Tree

    Definition Classes
      GenPositions

57. #### def reifyProduct(prefix: String, elements: List[Any]): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

58. #### def reifyProduct(x: Product): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

59. #### def reifySymDef(sym: tools.nsc.Global.Symbol): tools.nsc.Global.Tree

    Definition Classes
      GenSymbols

60. #### def reifySymRef(sym: tools.nsc.Global.Symbol): tools.nsc.Global.Tree

    Reify a reference to a symbol

    Reify a reference to a symbol

    Definition Classes
      GenSymbols

61. #### def reifyTree(tree: tools.nsc.Global.Tree): tools.nsc.Global.Tree

    Reify a tree.

    Reify a tree. For internal use only, use `reified` instead.

    Definition Classes
      GenTrees

62. #### def reifyTreeSymbols: Boolean

    Definition Classes
      GenTrees

63. #### def reifyTreeSyntactically(tree: tools.nsc.Global.Tree): tools.nsc.Global.Tree

    Definition Classes
      GenTrees

64. #### def reifyTreeTypes: Boolean

    Definition Classes
      GenTrees

65. #### def reifyType(tpe: tools.nsc.Global.Type): tools.nsc.Global.Tree

    Reify a type.

    Reify a type. For internal use only, use `reified` instead.

    Definition Classes
      GenTypes

66. #### val reshape: tools.nsc.Global.Transformer { ... /* 2 definitions in type refinement */ }

    Rolls back certain changes that were introduced during typechecking of the reifee.

    Rolls back certain changes that were introduced during typechecking of the reifee.

    These include: * Undoing macro expansions * Replacing type trees with TypeTree(tpe) * Reassembling CompoundTypeTrees into reifiable form * Transforming Modifiers.annotations into Symbol.annotations * Transforming Annotated annotations into AnnotatedType annotations * Transforming Annotated(annot, expr) into Typed(expr, TypeTree(Annotated(annot, _)) * Non-idempotencies of the typechecker: https://issues.scala-lang.org/browse/SI-5464

    Definition Classes
      Reshape

67. #### def scalaFactoryCall(name: String, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

68. #### def scalaFactoryCall(name: tools.nsc.Global.TermName, args: tools.nsc.Global.Tree*): tools.nsc.Global.Tree

    Definition Classes
      GenUtils

69. #### def spliceType(tpe: tools.nsc.Global.Type): tools.nsc.Global.Tree

    Definition Classes
      GenTypes

70. #### def symtab: Reifier.SymbolTable

    Symbol table of the reifee.

    Symbol table of the reifee.

    Keeps track of auxiliary symbols that are necessary for this reification session. These include: 1) Free vars (terms, types and existentials), 2) Non-locatable symbols (sometimes, e.g. for RefinedTypes, we need to reify these; to do that we create their copies in the reificode) 3) Non-locatable symbols that are referred by #1, #2 and #3

    Exposes three main methods: 1) `syms` that lists symbols belonging to the table, 2) `symXXX` family of methods that provide information about the symbols in the table, 3) `encode` that renders the table into a list of trees (recursively populating #3 and setting up initialization code for #1, #2 and #3)

    Definition Classes
      GenSymbols

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

    Definition Classes
      AnyRef

72. #### def termPath(fullname: String): tools.nsc.Global.Tree

    An (unreified) path that refers to term definition with given fully qualified name

    An (unreified) path that refers to term definition with given fully qualified name

    Definition Classes
      GenUtils

73. #### def toString(): String

    Definition Classes
      AnyRef → Any

74. #### final def wait(): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

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

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

76. #### final def wait(arg0: Long): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

77. #### def →[B](y: B): (Phases, B)

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

### Inherited from Reify

### Inherited from GenUtils

### Inherited from GenPositions

### Inherited from GenAnnotationInfos

### Inherited from GenTrees

### Inherited from GenNames

### Inherited from GenTypes

### Inherited from GenSymbols

### Inherited from Metalevels

### Inherited from Calculate

### Inherited from Reshape

### Inherited from AnyRef

### Inherited from Any

### Inherited by implicit conversion any2stringadd from Phases to any2stringadd[Phases]

### Inherited by implicit conversion StringFormat from Phases to StringFormat[Phases]

### Inherited by implicit conversion Ensuring from Phases to Ensuring[Phases]

### Inherited by implicit conversion ArrowAssoc from Phases to ArrowAssoc[Phases]

### Ungrouped