trait Enclosures extends AnyRef
EXPERIMENTAL
A slice of the Scala macros context that exposes enclosing trees (method, class, compilation unit and currently compiled macro application), the enclosing position of the macro expansion, as well as macros and implicits that are currently in-flight.
Starting from Scala 2.11.0, the APIs to get the trees enclosing by the current macro application are deprecated,
and the reasons for that are two-fold. Firstly, we would like to move towards the philosophy of locally-expanded macros,
as it has proven to be important for understanding of code. Secondly, within the current architecture of scalac,
we are unable to have c.enclosingTree-style APIs working robustly. Required changes to the typechecker would greatly
exceed the effort that we would like to expend on this feature given the existence of more pressing concerns at the moment.
This is somewhat aligned with the overall evolution of macros during the 2.11 development cycle, where we played with
c.introduceTopLevel
and c.introduceMember
, but at the end of the day decided to reject them.
If you're relying on the now deprecated APIs, consider using the new Internals.ContextInternalApi.enclosingOwner method that can be used to obtain the names of enclosing definitions. Alternatively try reformulating your macros in terms of completely local expansion and/or joining a discussion of a somewhat related potential language feature at https://groups.google.com/forum/#!topic/scala-debate/f4CLmYShX6Q. We also welcome questions and suggestions on our mailing lists, where we would be happy to further discuss this matter.
- Self Type
- blackbox.Context
- Source
- Enclosures.scala
- Alphabetic
- By Inheritance
- Enclosures
- AnyRef
- Any
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- Hide All
- Show All
- Public
- Protected
Deprecated Type Members
- case class EnclosureException(expected: Class[_], enclosingTrees: List[blackbox.Context.Tree]) extends Exception with Product with Serializable
Indicates than one of the enclosure methods failed to find a tree of required type among enclosing trees.
Indicates than one of the enclosure methods failed to find a tree of required type among enclosing trees.
- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
Abstract Value Members
- abstract def enclosingMacros: List[blackbox.Context]
Contexts that represent macros in-flight, including the current one.
Contexts that represent macros in-flight, including the current one. Very much like a stack trace, but for macros only. Can be useful for interoperating with other macros and for imposing compiler-friendly limits on macro expansion.
Is also priceless for emitting sane error messages for macros that are called by other macros on synthetic (i.e. position-less) trees. In that dire case navigate the
enclosingMacros
stack, and it will most likely contain at least one macro with a position-ful macro application. SeeenclosingPosition
for a default implementation of this logic.Unlike
openMacros
, this is a val, which means that it gets initialized when the context is created and always stays the same regardless of whatever happens during macro expansion. - abstract def enclosingPosition: blackbox.Context.Position
Tries to guess a position for the enclosing application.
Tries to guess a position for the enclosing application. But that is simple, right? Just dereference
pos
ofmacroApplication
? Not really. If we're in a synthetic macro expansion (no positions), we must do our best to infer the position of something that triggered this expansion. Surprisingly, quite often we can do this by navigation theenclosingMacros
stack. - abstract def macroApplication: blackbox.Context.Tree
The tree that undergoes macro expansion.
The tree that undergoes macro expansion. Can be useful to get an offset or a range position of the entire tree being processed.
- abstract def enclosingClass: blackbox.Context.Tree
Tree that corresponds to the enclosing class, or EmptyTree if not applicable.
Tree that corresponds to the enclosing class, or EmptyTree if not applicable.
- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingDef: Universe.DefDef
Tree that corresponds to the enclosing DefDef tree.
Tree that corresponds to the enclosing DefDef tree. Throws
EnclosureException
if there's no such enclosing tree.- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingImpl: Universe.ImplDef
Tree that corresponds to the enclosing ImplDef tree (i.e.
Tree that corresponds to the enclosing ImplDef tree (i.e. either ClassDef or ModuleDef). Throws
EnclosureException
if there's no such enclosing tree.- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingMethod: blackbox.Context.Tree
Tree that corresponds to the enclosing method, or EmptyTree if not applicable.
Tree that corresponds to the enclosing method, or EmptyTree if not applicable.
- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingPackage: Universe.PackageDef
Tree that corresponds to the enclosing PackageDef tree.
Tree that corresponds to the enclosing PackageDef tree. Throws
EnclosureException
if there's no such enclosing tree.- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingRun: blackbox.Context.Run
Compilation run that contains this macro application.
Compilation run that contains this macro application.
- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingTemplate: Universe.Template
Tree that corresponds to the enclosing Template tree.
Tree that corresponds to the enclosing Template tree. Throws
EnclosureException
if there's no such enclosing tree.- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
- abstract def enclosingUnit: blackbox.Context.CompilationUnit
Compilation unit that contains this macro application.
Compilation unit that contains this macro application.
- Annotations
- @deprecated
- Deprecated
(Since version 2.11.0) c.enclosingTree-style APIs are now deprecated; consult the scaladoc for more information
- See also
Concrete Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##(): Int
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- Implicit
- This member is added by an implicit conversion from Enclosures toany2stringadd[Enclosures] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
- def ->[B](y: B): (Enclosures, B)
- Implicit
- This member is added by an implicit conversion from Enclosures toArrowAssoc[Enclosures] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
- def ensuring(cond: (Enclosures) => Boolean, msg: => Any): Enclosures
- Implicit
- This member is added by an implicit conversion from Enclosures toEnsuring[Enclosures] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: (Enclosures) => Boolean): Enclosures
- Implicit
- This member is added by an implicit conversion from Enclosures toEnsuring[Enclosures] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean, msg: => Any): Enclosures
- Implicit
- This member is added by an implicit conversion from Enclosures toEnsuring[Enclosures] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean): Enclosures
- Implicit
- This member is added by an implicit conversion from Enclosures toEnsuring[Enclosures] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- def formatted(fmtstr: String): String
- Implicit
- This member is added by an implicit conversion from Enclosures toStringFormat[Enclosures] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @inline()
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- AnyRef → Any
- 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()
Deprecated Value Members
- def →[B](y: B): (Enclosures, B)
- Implicit
- This member is added by an implicit conversion from Enclosures toArrowAssoc[Enclosures] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
->
instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.