Robert Haas <robertmhaas@gmail.com> writes: > I (still) think this is a bad design. Even if you've got all the > messages just right as things stand today, some new feature that comes > along in the future can change things so that they're not right any > more, and nobody's going to relish maintaining this.
FWIW, I tend to agree that this is way overboard in terms of the amount of complexity going into the messages. Also, I do not like what seems to be happening here: >> $ psql test < test2.sql -v ON_ERROR_STOP=0 >> unrecognized value "error" for "\if <expr>": boolean expected >> new \if is invalid, ignoring commands until next \endif
IMO, an erroneous backslash command should have no effect, period. "It failed but we'll treat it as if it were valid" is a rathole I don't want to descend into. It's particularly bad in interactive mode, because the most natural thing to do is correct your spelling and issue the command again --- but if psql already decided to do something on the strength of the mistaken command, that doesn't work, and you'll have to do something or other to unwind the unwanted control state before you can get back to what you meant to do.
regards, tom lane
One way around this is to make the small change: commands with invalid expressions are ignored in interactive mode.
Another way around it would be to ignore branching commands in interactive mode altogether and give a message like "branching commands not supported in interactive mode". That'd get rid of a lot of complexity right there. I for one wouldn't miss it. The only use I saw for it was debugging a script, and in that case the user can be their own branching via selective copy/paste.
