Debugging tool like Ruby's pry. Insert one themod call break cause interuption of program and setup scala interactive tool (Repl) with bound values. User can show the value, call methods and change internal state of it.

build.sbt

libraryDependencies += "com.github.bigwheel" %% "thpy" % "0.1.0"

Write code as sample Main.scala,

import com.github.bigwheel.thpy.break
import com.github.bigwheel.thpy.Macro.anyToTyped

// for human interactive test purpose Main.
object Main {
  def main(args: Array[String]): Unit = {
    val a = 10
    break(a)
  }
}

then sbt run and interact with thpy console

$ sbt run
....
Welcome to Thpy at <empty>.Main.main(/home/kbigwheel/code/thpy-sample/src/main/scala/Main.scala:8)

    4:
    5:   def main(args: Array[String]): Unit = {
    6:     val a = 10
=>  7:     break(a)
    8:   }
    9:
   10: }

bound names: a
Type in expressions for evaluation. Or try :help.

thpy> a
res0: Int = 10

thpy> 1 + 1
res1: Int = 2

thpy> a + 2
res2: Int = 12

thpy> :quit

Tested only in 2.12. And this must not work well in other version because repl code has no compatibility.

Type of binded value must be visible in public scope. There private class, enclosing class or annonymous class cannot be used in thpy (public class with private constructor is no problem).