This patch adds two very simple psql commands: \quit_if and \quit_unless.
A few comments about the feature design:
I'm unsure about the name, esp with '_'. There are some \lo_* commands, but others rely on pasted words (\crosstabview, \errverbose, ...).
There are not any other conditional statements - so using "_" can be better
I'm wondering if an simplistic interpreted \if \elsif/\else \fi would make more sense:
The \if \ese \elseif is not in contradiction with \quit_if - \if is more generic, \quit_if is simple for implementation, one liner, and best readable
Pavel
Quitting seems a little bit definitive, and means that if I have some alternatives then I have to have something that relaunch another script outside...
When \includes are process, does \quit stop the include or the full script. I'm afraid it is the script.
Now probably an \if... would have also some drawbacks, but ISTM that there could be less of them.