/
language.scala
180 lines (156 loc) · 7.23 KB
/
language.scala
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package scala.runtime.stdLibPatches
import scala.annotation.compileTimeOnly
/** Scala 3 additions and replacements to the `scala.language` object.
*/
object language:
/** The experimental object contains features that have been recently added but have not
* been thoroughly tested in production yet.
*
* Experimental features '''may undergo API changes''' in future releases, so production
* code should not rely on them.
*
* Programmers are encouraged to try out experimental features and
* [[http://issues.scala-lang.org report any bugs or API inconsistencies]]
* they encounter so they can be improved in future releases.
*
* @group experimental
*/
object experimental:
/* Experimental support for richer dependent types (disabled for now)
* One can still run the compiler with support for parsing singleton applications
* using command line option `-language:experimental.dependent`.
* But one cannot use a feature import for this as long as this entry is commented out.
*/
//object dependent
/** Experimental support for named type arguments.
*
* @see [[https://dotty.epfl.ch/docs/reference/other-new-features/named-typeargs]]
*/
@compileTimeOnly("`namedTypeArguments` can only be used at compile time in import statements")
object namedTypeArguments
/** Experimental support for generic number literals.
*
* @see [[https://dotty.epfl.ch/docs/reference/changed-features/numeric-literals]]
*/
@compileTimeOnly("`genericNumberLiterals` can only be used at compile time in import statements")
object genericNumberLiterals
/** Experimental support for `erased` modifier
*
* @see [[https://dotty.epfl.ch/docs/reference/experimental/erased-defs]]
*/
@compileTimeOnly("`erasedDefinitions` can only be used at compile time in import statements")
object erasedDefinitions
/** Experimental support for using indentation for arguments
*/
@compileTimeOnly("`fewerBraces` can only be used at compile time in import statements")
object fewerBraces
/** Experimental support for typechecked exception capabilities
*
* @see [[https://dotty.epfl.ch/docs/reference/experimental/canthrow]]
*/
@compileTimeOnly("`saferExceptions` can only be used at compile time in import statements")
object saferExceptions
end experimental
/** The deprecated object contains features that are no longer officially suypported in Scala.
* Features in this object are slated for removal. New code should not use them and
* old code should migrate away from them.
*/
@compileTimeOnly("`deprecated` can only be used at compile time in import statements")
object deprecated:
/** Symbol literals have been deprecated since 2.13. Since Scala 3.0 they
* are no longer an official part of Scala. For compatibility with legacy software,
* symbol literals are still supported with a language import, but new software
* should not use them.
*/
@compileTimeOnly("`symbolLiterals` can only be used at compile time in import statements")
object symbolLiterals
end deprecated
/** Where imported, auto-tupling is disabled.
*
* '''Why control the feature?''' Auto-tupling can lead to confusing and
* brittle code in presence of overloads. In particular, surprising overloads
* can be selected, and adding new overloads can change which overload is selected
* in suprising ways.
*
* '''Why allow it?''' Not allowing auto-tupling is difficult to reconcile with
* operators accepting tuples.
*/
@compileTimeOnly("`noAutoTupling` can only be used at compile time in import statements")
object noAutoTupling
/** Where imported, loose equality using eqAny is disabled.
*
* '''Why allow and control the feature?''' For compatibility and migration reasons,
* strict equality is opt-in. See linked documentation for more information.
*
* @see [[https://dotty.epfl.ch/docs/reference/contextual/multiversal-equality]]
*/
@compileTimeOnly("`strictEquality` can only be used at compile time in import statements")
object strictEquality
/** Where imported, ad hoc extensions of non-open classes in other
* compilation units are allowed.
*
* '''Why control the feature?''' Ad-hoc extensions should usually be avoided
* since they typically cannot rely on an "internal" contract between a class
* and its extensions. Only open classes need to specify such a contract.
* Ad-hoc extensions might break for future versions of the extended class,
* since the extended class is free to change its implementation without
* being constrained by an internal contract.
*
* '''Why allow it?''' An ad-hoc extension can sometimes be necessary,
* for instance when mocking a class in a testing framework, or to work
* around a bug or missing feature in the original class. Nevertheless,
* such extensions should be limited in scope and clearly documented.
* That's why the language import is required for them.
*/
@compileTimeOnly("`adhocExtensions` can only be used at compile time in import statements")
object adhocExtensions
/** Unsafe Nulls fot Explicit Nulls
* Inside the "unsafe" scope, `Null` is considered as a subtype of all reference types.
*
* @see [[http://dotty.epfl.ch/docs/reference/other-new-features/explicit-nulls.html]]
*/
@compileTimeOnly("`unsafeNulls` can only be used at compile time in import statements")
object unsafeNulls
@compileTimeOnly("`future` can only be used at compile time in import statements")
object future
@compileTimeOnly("`future-migration` can only be used at compile time in import statements")
object `future-migration`
/** Set source version to 3.0-migration.
*
* @see [[https://docs.scala-lang.org/scala3/guides/migration/compatibility-intro.html]]
*/
@compileTimeOnly("`3.0-migration` can only be used at compile time in import statements")
object `3.0-migration`
/** Set source version to 3.0.
*
* @see [[https://docs.scala-lang.org/scala3/guides/migration/compatibility-intro.html]]
*/
@compileTimeOnly("`3.0` can only be used at compile time in import statements")
object `3.0`
/** Set source version to 3.1-migration.
*
* @see [[https://docs.scala-lang.org/scala3/guides/migration/compatibility-intro.html]]
*/
@compileTimeOnly("`3.1-migration` can only be used at compile time in import statements")
object `3.1-migration`
/** Set source version to 3.1
*
* @see [[https://docs.scala-lang.org/scala3/guides/migration/compatibility-intro.html]]
*/
@compileTimeOnly("`3.1` can only be used at compile time in import statements")
object `3.1`
/* This can be added when we go to 3.2
/** Set source version to 3.2-migration.
*
* @see [[https://scalacenter.github.io/scala-3-migration-guide/docs/scala-3-migration-mode]]
*/
@compileTimeOnly("`3.2-migration` can only be used at compile time in import statements")
object `3.2-migration`
/** Set source version to 3.2
*
* @see [[https://scalacenter.github.io/scala-3-migration-guide/docs/scala-3-migration-mode]]
*/
@compileTimeOnly("`3.2` can only be used at compile time in import statements")
object `3.2`
*/
end language