How to define an environment value witih : in name in docker compose?

Question

I would like to pass an environment variable named ABC:DEF to a container defined in a docker-compose.yml.

How to do it?

If I write in a service definition

environment:
    ABC:DEF: ${ABC:DEF}

I got

ERROR: Invalid interpolation format for "environment" option in service: "${ABC:DEF}"

Edit: The goal of this question is to understand whether it is possible to use environment variables names which contain a : colon and how to properly define that in docker-compose.yml. A discussion what are the alternatives to using the : colon from the view of the "thing" running inside the affected container is not part of the question.

Answer 1

Use the following line instead of ABC:DEF: ${ABC:DEF}:

environment:
  POSTGRES_PASSWORD: any-password 

---

[UPDATE]:

If : cannot be used in environment variables in your system, replace : with __ (double underscore).

Configuration_in _ASP.NET _Core_Reference

So I think that would be something like this:

ABC__DEF: <asp-environment>