Can i use variable expansion/interpolation in CI pipeline variables?

I’d like know if i could use something like this:

variables:
  INSTANCE_VALUE: ${GLOBAL_VALUE:-default}

So, if GLOBAL_VALUE is not set, or has no content, INSTANCE_VALUE should be loaded with the string “default” (this is just an example).

When i do it that way, INSTANCE_VALUE will always be empty.

Some discussions in