Pavel Stehule:
looks a little bit obscure - why do you need to do it from psql? And how frequently do you do it?
I store all my SQL code in git and use "psql -e" to "bundle" it into an extension, which is then deployed to production.
The code is spread over many files, which include other files via \ir. Sometimes you need to include other types of files, though - for example code in other languages as Steve mentioned, but I have also had cases for yaml files, markdown templates, even binary assets which should still be considered "code" and not data.
So anything in that direction would help.
