Bug in parser

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                        POSTGRESQL BUG REPORT TEMPLATE
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Your name        :    Andriy I Pilipenko
Your email address    :    bamby@marka.net.ua


System Configuration
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  Architecture (example: Intel Pentium)      :    i486 and higher

  Operating System (example: Linux 2.0.26 ELF)     :    FreeBSD 2.2.6
                            FreeBSD 2.2.7
                            Linux 2.0.34 ELF

  PostgreSQL version (example: PostgreSQL-6.4.2)  :       PostgreSQL-6.4
                            PostgreSQL-6.4.2

  Compiler used (example:  gcc 2.8.0)        :    gcc 2.7.2.1


Please enter a FULL description of your problem:
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Backend reports syntax error near unary '-' in queries like:

    SELECT * FROM some_table WHERE some_column IN ( <negative number> )
                           ^^^^^^^^^^^^^^^^^^^^^^^^
This bug not existed in 6.3.2. It first appeared in 6.4 and remains in
6.4.2.


Please describe a way to repeat the problem.   Please try to provide a
concise reproducible example, if at all possible:
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Bug is very easy to reproduce. See query above.



If you know how this problem might be fixed, list the solution below:
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