Handling varargs in macros

[anatoliykmetyuk]

No description provided.

[nicolasstucki]

import scala.quoted._
import scala.quoted.matching.{ExprSeq, ConstSeq}

inline def foo(xs: Int*) = ${ impl('xs) }

def impl(xs: Expr[Seq[Int]]) given QuoteContext: Expr[Unit] = xs match {
   case ExprSeq(xs2) => xs2: Seq[Expr[Int]] // example: foo(arg1, arg2, arg3)
  case _ =>  // example: foo(args: _*)
}

def impl2(xs: Expr[Seq[Int]]) given QuoteContext: Expr[Unit] = xs match {
   case ConstSeq(xs2) => xs2: Seq[Int] // example: foo(1, 2, 3)
  case _ =>  // example: foo(args: _*) or foo(arg1, arg2, arg3)
}

[nicolasstucki]

def f(xs: List[Int]) given QuoteContext: Expr[List[Int]] = 
  '{ List(${xs.toSeq.toExpr}: _*) } // lifted Seq is optimal for varargs