If there is one Lisp function/macro/feature that you would like to see in a non-Lisp language, which one would it be? - eviltoast

This is another Friday social topic. You are aimlessly wandering around a beautiful hilltop by a sea when an angel approaches you from the opposite direction. She is no ordinary angel. She is a Lisp angel! She will grant one Lisp wish to you. Before she can fulfill your wish, she needs this information from you:

  1. Your favorite Lisp dialect.
  2. Your favorite non-Lisp programming language.
  3. Your favorite standard library function/macro/feature from your favorite Lisp dialect that you want to see in your favorite non-Lisp programming language.

Once you tell these 3 things to the angel, she will magically add your chosen feature to your chosen non-Lisp programming language.

What are your answers going to be?