Can an overlay change a function definition?

[scastria]

Suppose I had a yml file that declared a function that is called throughout that yml file. Can I add an overlay that redefines that function to have different content?

[prembhaskal]

I think it cannot.
If you see here https://carvel.dev/ytt/docs/v0.49.x/how-it-works/ , overlay works on top of evaluated templates. Evaluated templates cannot have function definition because ytt does not emit comments, and all functions are defined as comments.

[renuy]

@scastria
for ytt clarifications, you can also reach out on #carvel in Kubernetes Slack