package dotty.tools
package dotc
package typer
import dotty.tools.dotc.ast.Trees.NamedArg
import dotty.tools.dotc.ast.tpd._
import dotty.tools.dotc.ast.untpd
import dotty.tools.dotc.core.Constants.Constant
import dotty.tools.dotc.core.Contexts.Context
import dotty.tools.dotc.core.Names.Name
import dotty.tools.dotc.core.StdNames._
import dotty.tools.dotc.core.Types._
import dotty.tools.dotc.core.Mode
import dotty.tools.dotc.core.Decorators._
object Dynamic {
def isDynamicMethod(name: Name): Boolean =
name == nme.applyDynamic || name == nme.selectDynamic || name == nme.updateDynamic || name == nme.applyDynamicNamed
}
/** Translates selection that does not typecheck according to the scala.Dynamic rules:
* foo.bar(baz) = quux ~~> foo.selectDynamic(bar).update(baz, quux)
* foo.bar = baz ~~> foo.updateDynamic("bar")(baz)
* foo.bar(x = bazX, y = bazY, baz, ...) ~~> foo.applyDynamicNamed("bar")(("x", bazX), ("y", bazY), ("", baz), ...)
* foo.bar(baz0, baz1, ...) ~~> foo.applyDynamic(bar)(baz0, baz1, ...)
* foo.bar ~~> foo.selectDynamic(bar)
*
* The first matching rule of is applied.
*/
trait Dynamic { self: Typer with Applications =>
/** Translate selection that does not typecheck according to the normal rules into a applyDynamic/applyDynamicNamed.
* foo.bar(baz0, baz1, ...) ~~> foo.applyDynamic(bar)(baz0, baz1, ...)
* foo.bar(x = bazX, y = bazY, baz, ...) ~~> foo.applyDynamicNamed("bar")(("x", bazX), ("y", bazY), ("", baz), ...)
*/
def typedDynamicApply(qual: untpd.Tree, name: Name, args: List[untpd.Tree], pt: Type)(original: untpd.Apply)(
implicit ctx: Context): Tree = {
def isNamedArg(arg: untpd.Tree): Boolean = arg match { case NamedArg(_, _) => true; case _ => false }
val dynName = if (args.exists(isNamedArg)) nme.applyDynamicNamed else nme.applyDynamic
if (dynName == nme.applyDynamicNamed && untpd.isWildcardStarArgList(args)) {
ctx.error("applyDynamicNamed does not support passing a vararg parameter", original.pos)
original.withType(ErrorType)
} else {
def namedArgTuple(name: String, arg: untpd.Tree) = untpd.Tuple(List(Literal(Constant(name)), arg))
def namedArgs = args.map {
case NamedArg(argName, arg) => namedArgTuple(argName.toString, arg)
case arg => namedArgTuple("", arg)
}
val args1 = if (dynName == nme.applyDynamic) args else namedArgs
typedApply(untpd.Apply(coreDynamic(qual, dynName, name), args1), pt)
}
}
/** Translate selection that does not typecheck according to the normal rules into a selectDynamic.
* foo.bar ~~> foo.selectDynamic(bar)
*
* Note: inner part of translation foo.bar(baz) = quux ~~> foo.selectDynamic(bar).update(baz, quux) is achieved
* through an existing transformation of in typedAssign [foo.bar(baz) = quux ~~> foo.bar.update(baz, quux)].
*/
def typedDynamicSelect(tree: untpd.Select, pt: Type)(implicit ctx: Context): Tree =
typedApply(coreDynamic(tree.qualifier, nme.selectDynamic, tree.name), pt)
/** Translate selection that does not typecheck according to the normal rules into a updateDynamic.
* foo.bar = baz ~~> foo.updateDynamic(bar)(baz)
*/
def typedDynamicAssign(qual: untpd.Tree, name: Name, rhs: untpd.Tree, pt: Type)(implicit ctx: Context): Tree =
typedApply(untpd.Apply(coreDynamic(qual, nme.updateDynamic, name), rhs), pt)
private def coreDynamic(qual: untpd.Tree, dynName: Name, name: Name)(implicit ctx: Context): untpd.Apply =
untpd.Apply(untpd.Select(qual, dynName), Literal(Constant(name.toString)))
}