gmethvin / fastforward   0.1.0

Apache License 2.0 GitHub

A Scala macro to generate forwarded instances of traits

Scala versions: 2.13 2.12


FastForward is a macro library that automatically implements traits or abstract classes by forwarding to another instance. It currently provides one macro called forward that generates an instance of a trait with abstract methods forwarded to a specific instance you pass to the macro.


For example, say I have a trait Foo that I want to implement. If I have an instance of a class Bar that contains members of the same name, forward will automatically generate the implementations of the abstract Foo methods to forward to the methods of the instance of Bar you passed.

import io.methvin.fastforward._

trait Foo {
  def foo: String
  def bar: Long
  val baz: Option[String]
class Bar {
  def foo = "foo"
  def bar: Long = 2
  def baz = Some("baz")
val bar = new Bar
val impl: Foo = forward[Foo](bar)