AmmPlay.scala

package playground


import ammonite.main
import ammonite.main.Scripts
import ammonite.ops._

object AmmPlay extends App {

  println("starting")

  val interpreter = ammonite.Main().instantiateInterpreter().right.get

  val result =
    Scripts.runScript(
      pwd,
      pwd / "hello-world.sc",
      interpreter,
    )

  println(result)

  println("complete")

}

hello-world.sc

@main
def foo() = {
    println("running foo")
    "return a string"
}

println("initializing foo")

stdout

starting
initializing foo
running foo
Success(return a string)
complete