diff options
Diffstat (limited to 'src/repl/scala/tools/nsc/interpreter/ReplVals.scala')
-rw-r--r-- | src/repl/scala/tools/nsc/interpreter/ReplVals.scala | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/src/repl/scala/tools/nsc/interpreter/ReplVals.scala b/src/repl/scala/tools/nsc/interpreter/ReplVals.scala new file mode 100644 index 0000000000..ea100b25f2 --- /dev/null +++ b/src/repl/scala/tools/nsc/interpreter/ReplVals.scala @@ -0,0 +1,82 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2013 LAMP/EPFL + * @author Paul Phillips + */ + +package scala.tools.nsc +package interpreter + +import scala.language.implicitConversions +import scala.reflect.api.{Universe => ApiUniverse} +import scala.reflect.runtime.{universe => ru} + +/** A class which the repl utilizes to expose predefined objects. + * The base implementation is empty; the standard repl implementation + * is StdReplVals. + */ +abstract class ReplVals { } + +class StdReplVals(final val r: ILoop) extends ReplVals { + final lazy val repl = r + final lazy val intp = r.intp + final lazy val power = r.power + final lazy val reader = r.in + final lazy val vals = this + final lazy val global: intp.global.type = intp.global + final lazy val isettings = intp.isettings + final lazy val completion = reader.completion + final lazy val history = reader.history + final lazy val phased = power.phased + final lazy val analyzer = global.analyzer + + object treedsl extends { val global: intp.global.type = intp.global } with ast.TreeDSL { } + + final lazy val typer = analyzer.newTyper( + analyzer.rootContext( + power.unit("").asInstanceOf[analyzer.global.CompilationUnit] + ) + ) + def lastRequest = intp.lastRequest + + class ReplImplicits extends power.Implicits2 { + import intp.global._ + + private val tagFn = ReplVals.mkCompilerTypeFromTag[intp.global.type](global) + implicit def mkCompilerTypeFromTag(sym: Symbol) = tagFn(sym) + } + + final lazy val replImplicits = new ReplImplicits + + def typed[T <: analyzer.global.Tree](tree: T): T = typer.typed(tree).asInstanceOf[T] +} + +object ReplVals { + /** Latest attempt to work around the challenge of foo.global.Type + * not being seen as the same type as bar.global.Type even though + * the globals are the same. Dependent method types to the rescue. + */ + def mkCompilerTypeFromTag[T <: Global](global: T) = { + import global._ + + /** We can't use definitions.compilerTypeFromTag directly because we're passing + * it to map and the compiler refuses to perform eta expansion on a method + * with a dependent return type. (Can this be relaxed?) To get around this + * I have this forwarder which widens the type and then cast the result back + * to the dependent type. + */ + def compilerTypeFromTag(t: ApiUniverse # WeakTypeTag[_]): Global#Type = + definitions.compilerTypeFromTag(t) + + class AppliedTypeFromTags(sym: Symbol) { + def apply[M](implicit m1: ru.TypeTag[M]): Type = + if (sym eq NoSymbol) NoType + else appliedType(sym, compilerTypeFromTag(m1).asInstanceOf[Type]) + + def apply[M1, M2](implicit m1: ru.TypeTag[M1], m2: ru.TypeTag[M2]): Type = + if (sym eq NoSymbol) NoType + else appliedType(sym, compilerTypeFromTag(m1).asInstanceOf[Type], compilerTypeFromTag(m2).asInstanceOf[Type]) + } + + (sym: Symbol) => new AppliedTypeFromTags(sym) + } +} |