Re: patch (for 9.1) string functions

>
> so "any" datatype is last possibility - is workaroud for custom functions.

Probably the most correct implementation of CONCAT have to contains a
parser changes - and then you can use a some internal concat function
with text only parameters. VARIADIC with "any" is just workaround that
is enouhg

Regards

Pavel

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>> The problem with your canonical example (and the other examples of
>> this type I've seen) is that they are underspecified.  Given two
>> identically-named operators, one of which accepts types T1 and T2, and
>> the other of which accepts types T3 and T4, what is one to do with T1
>> OP T4?  You can cast T1 to T3 and call the first operator or you can
>> cast T4 to T2 and call the second one, and it's really not clear which
>> is right, so you had better thrown an error.  The same applies to
>> functions: given foo(text) and foo(date) and the call
>> foo('2010-04-15'), you had better complain, or you may end up with a
>> very sad user.  But sometimes our current casting rules require casts
>> in situations where they don't seem necessary, such as
>> LPAD(integer_column, '0', 5).  That's not ambiguous because there's
>> only one definition of LPAD, and the chances that the user will be
>> unpleasantly surprised if you call it seem quite low.
>>
>> In other words, this problem is not unique to CONCAT().
>>
>> --
>> Robert Haas
>> EnterpriseDB: http://www.enterprisedb.com
>> The Enterprise Postgres Company
>>
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