Re: \if, \elseif, \else, \endif (was Re: [HACKERS] PSQL commands:\quit_if, \quit_unless)

I noticed that the "barking" is conditional to "success". ISTM that it should always "bark" in interactive mode, whether success or not.

While testing it and seeing the code, I agree that it is too verbose/redundant. At least remove "active/inactive, ".

- Help text. New block in help text called "Conditionals"

Maybe it could be moved to "Input/Output" renamed as "Input/Output Control", or maybe the "Conditionals" section could be moved next to it, it seems more logical than after large objects.

I think that the descriptions are too long. The interactive user can be trusted to know what "if/elif/else/endif" mean, or to refer to the full documentation otherwise. The point is just to provide a syntax and function reminder, not a substitute for the doc. Thus I would suggest shorter one-line messages like:

 \if <expr>    begin a new conditional block
 \elif <expr>  else if in the current conditional block
 \else         else in current conditional block
 \endif        end current conditional block

Hmmm. Perl is perl. Attached an attempt at improving that, which is probably debatable, but at least it is easy to add further tests without massive copy-pasting.

- regression tests now have comments to explain purpose

Ok.

Small details about the code:

  +       if (!pset.active_branch && !is_branching_command(cmd) )

Not sure why there is a space before the last closing parenthesis.