Обсуждение: Error in ECPG and #if...

    Hi all,

    I use ECPG distributed with PostgreSQL 6.4.2. and I found next
error..:-(

    ECPG don't know C/C++ preprocessing directives such as #if, #ifdef
etc...

I try this:

..
...
15. #if 0
16. exec sql select count (*) from
17. exec sql commit;
18. #endif

    In this ECPG  say: parse error on line 16.

    But when I use this:
15. // exec sql select count (*) from
16. // exec sql commit;

    ECPG parse this correctly...

    I think, that this is wrong, that ECPG use as comment only /* and //
comment. Construction such as #if 0 is very common way to disable some
source and enable this later... - mainly in debugging proces, of cource.

    Or do I something wrong?

    Thanks...

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> ECPG don't know C/C++ preprocessing directives such as #if, #ifdef
> etc...
>     I think, that this is wrong, that ECPG use as comment only /* and //
> comment. Construction such as #if 0 is very common way to disable some
> source and enable this later... - mainly in debugging proces, of cource.

... but this is not common for ESQL preprocessors. The problem is that
the preprocessor runs before the C/C++ preprocessor, which is the step
which actually handles the #if constructs. ecpg has no knowledge of
those constructs. Remember that to do those correctly one must also
resolve all other preprocessor kinds of things, like #include
directives.

                       - Tom

--
Thomas Lockhart                lockhart@alumni.caltech.edu
South Pasadena, California

On Tue, Apr 20, 1999 at 05:59:13PM +0200, Pavel PaJaSoft Janousek wrote:
>     I use ECPG distributed with PostgreSQL 6.4.2. and I found next
> error..:-(

Not really.

>     ECPG don't know C/C++ preprocessing directives such as #if, #ifdef
> etc...

That's correct. ECPG only parses stuff between EXEC SQL and ';'.

> 15. #if 0
> 16. exec sql select count (*) from
> 17. exec sql commit;
> 18. #endif

This is not C code.

>     In this ECPG  say: parse error on line 16.

Yes, because ECPG parses all embedded SQL code. It does not know about cpp
code.

Michael

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Michael Meskes                         | Go SF 49ers!
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