Problem with ecpg

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POSTGRESQL BUG REPORT TEMPLATE
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Your name : Bernard Isambert
Your email address : isambert(at)sib(dot)fr

System Configuration
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Architecture (example: Intel Pentium) : Intel pentium

Operating System (example: Linux 2.0.26 ELF) : Linux 2.2.13

PostgreSQL version (example: PostgreSQL-6.5.3): PostgreSQL-7.0beta5
(and previous)

Compiler used (example: gcc 2.8.0) : any...

Please enter a FULL description of your problem:
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The problem is in the parsing of operators by ecpg (details below).
As a result, good or bad precompile depends on usage of spaces
in the source, where it should not.

Please describe a way to repeat the problem. Please try to provide a
concise reproducible example, if at all possible:
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Source file:

EXEC SQL BEGIN DECLARE SECTION;
VARCHAR hostvar[32];
EXEC SQL END DECLARE SECTION;

strcpy(hostvar.arr, "something");

EXEC SQL SELECT column2 FROM table1 WHERE column1 = :hostvar;

strcpy(hostvar.arr, "anything");

EXEC SQL SELECT column2 FROM table1 WHERE column1=:hostvar;

Ecpg parsing gives:

for the first select, with spaces around the = sign:

{ ECPGdo(__LINE__, NULL, "select column2 from table1 where column1 =
? ",
ECPGt_varchar,&(hostvar),32L,1L,sizeof(struct varchar_hostvar),
ECPGt_NO_INDICATOR, NULL, 0L, 0L, 0L, ECPGt_EOIT, ECPGt_EORT);}

for the second select, without spaces around (after) the = sign:

{ ECPGdo(__LINE__, NULL, "select column2 from table1 where column1
=: hostvar ",
ECPGt_EOIT, ECPGt_EORT);}

which is clearly different from the expected result
and yields a run-time error ...

If you know how this problem might be fixed, list the solution below:
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I suggest a workaround in the ecpg source "pgc.l"
(src/interfaces/ecpg/preproc/pgc.l):

diff pgc.l.orig pgc.l
192c192,194
< operator {op_chars}+
---
> /* op_mchars = op_chars but the ':' */
> op_mchars [\~\!\(at)\#\^\&\|\`\?\$\+\-\*\\/\%\<\>\=]
> operator {op_chars}{op_mchars}*

This forbids ":" to be the second (or above) char in an operator.
Is there any situation where it should be?
Or maybe the rule should be a bit more complex?

--
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Bernard ISAMBERT (isambert(at)sib(dot)fr)
Syndicat Interhospitalier de Bretagne (www.sib.fr)
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