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

Hello Corey,

> It doesn't strike me as much cleaner, but it's no worse, either.

Hmmm.

The "if (x) { x = ... ; if (x) {" does not help much to improve 
readability and understandability...

My 0.02€ about v19:

If there are two errors, I do not care which one is shown, both will have 
to be fixed anyway in the end... So I would suggest to choose the simplest 
possible implementation:

   on elif:
     always eval expression
       => possible eval error
     switch
       => including detecting misplaced elif errors

If the second error must absolutely be shown in all cases, then add a 
second misplaced elif detection in the eval expression failure branch:

   on elif
     always eval
     if (eval failed)
       also checked for misplaced (hey user, you have 2 errors in fact...)
       bye bye...
     // else eval was fine
     switch
       including misplaced elif detection

If the committer is angry at these simple approach, then revert to the 
strange looking and hard to understand switch-if-switch solution (~ v18, 
or some simplified? v19), but I do not think the be weak benefit is worth 
the code complexity.

-- 
Fabien.