Re: IF (NOT) EXISTS in psql-completion - Mailing list pgsql-hackers

At Thu, 31 Mar 2016 11:22:20 +0200, Pavel Stehule <pavel.stehule@gmail.com> wrote in <CAFj8pRD7vADuNOiApB8Exwc+C5cCis-rj2dPhvZCwZKgXjb_Xg@mail.gmail.com>

> 2016-03-30 10:34 GMT+02:00 Kyotaro HORIGUCHI <
> horiguchi.kyotaro@lab.ntt.co.jp>:
>
> > Hi,
> >
> > At Wed, 30 Mar 2016 09:23:49 +0200, Pavel Stehule <pavel.stehule@gmail.com>
> > wrote in <
> > CAFj8pRBVKa6NG4JwZ2QmrO7inudFJws5w0+demVgZZNuF-HUkQ@mail.gmail.com>
> > > Hi
> > >
> > > ...
> > > >> =# alter table if<tab>
> > > >> =# alter table if exists
> > > >> ======
> > > >> =# alter table I<tab>
> > > >> =# alter table IF EXISTS    // "information_schema" doesn't match.
> > > >>
> > > >> Since this is another problem from IF (NOT) EXISTS, this is
> > > >> in separate form.
> > > >>
> > > >> What do you think about this?
> > > >>
> > > >
> > > > +1
> > > >
> > >
> > > The new behave is much better.
> >
> > I'm glad to hear that.
> >
> > > I found new warning
> > >
> > >  tab-complete.c:1438:87: warning: right-hand operand of comma expression
> > > has no effect [-Wunused-value]
> >
> > Mmm. Google said me that gcc 4.9 does so. I'm using 4.8.5 so I
> > haven't see the warning.
> >
> > https://gcc.gnu.org/gcc-4.9/porting_to.html
> >
> > 1436:   else if (HeadMatches2("CREATE", "SCHEMA") &&
> > 1437:                    SHIFT_TO_LAST1("CREATE") &&
> > 1438:                    false) {} /* FALL THROUGH */
> >
> > > #define SHIFT_TO_LAST1(p1) \
> > >     (HEADSHIFT(find_last_index_of(p1, previous_words,
> > previous_words_count)), \
> > >      true)
> >
> > > #define HEADSHIFT(n) \
> > >     (head_shift += n, true)
> >
> > expanding the macros the lines at the error will be
> >
> > else if (HeadMatches2("CREATE", "SCHEMA") &&
> >          (head_shift +=
> >           find_last_index_of("CREATE", previous_words,
> > previous_words_count),
> >            true) &&
> >          false) {} /* FALL THROUGH */
> >
> > But the right hand value (true) is actually "used" in the
> > expression (even though not effective). Perhaps (true && false)
> > was potimized as false and the true is regarded to be unused?
> > That's stupid.. Using functions instead of macros seems to solve
> > this but they needed to be wraped by macros as
> > additional_kw_query(). That's a pain..
> >
> > Any thougts?
> >
> > > There is small minor issue - I don't know if it is solvable. Autocomplete
> > > is working only for "if" keyword. When I am writing "if " or "if " or "if
> > > exi" - then autocomplete doesn't work. But this issue is exactly same for
> > > other "multi words" completation like  "alter foreign data wrapper". So
> > if
> > > it is fixable, then it can be out of scope this patch.
> >
> > Yes.  It can be saved only by adding completion for every word,
> > as some of the similar completion is doing.
> >
> > > anything else looks well.
> >
> > Thanks.
> >
>
> please, final patch

This needs to use gcc 4.9 to address, but CentOS7 doesn't have
devtools-2 repo so now I'm building CentOS6 environment for this
purpose. Please wait for a while.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center