Scala 2 compat: enable reflectiveSelectable for language.reflectiveCalls. #9420
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…lls. In Scala 2, calls to structural types that require reflective calls must be enabled with import scala.language.reflectiveCalls In Scala 3, that import has no effect, and reflective calls refuse to compile without the following import: import scala.reflect.Selectable.reflectiveSelectable However, since that import does not compile in Scala 2, there is no way to write code that cross-compiles between Scala 2 and Scala 3 and uses reflective calls to members of structural types. In this commit, we conditionally enable `reflectiveSelectable` if a given `scala.language.reflectiveCalls` is in scope. This straightforwardly allows code to cross-compile by using the Scala 2 language import, without any compiler intervention.
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odersky
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In Scala 2, calls to structural types that require reflective calls must be enabled with
In Scala 3, that import has no effect, and reflective calls refuse to compile without the following import:
However, since that import does not compile in Scala 2, there is no way to write code that cross-compiles between Scala 2 and Scala 3 and uses reflective calls to members of structural types.
In this commit, we conditionally enable
reflectiveSelectableif a givenscala.language.reflectiveCallsis in scope. This straightforwardly allows code to cross-compile by using the Scala 2 language import, without any compiler intervention.