Hmm, can't we just use

el=${dir#$base_dir}

We probably can, there are more things which could be nicer. I just tried to keep the spirit.

One of you guys needs to move

I am ok with both variant. However in case of rewriting, I would go for a lot more rewrites, so that patch would be bigger.

Beeeeep.

Accept or remake, that's here the question....

Hello?

@mlschroe: review reminder