Re: expression evaluation with expected datatypes

Excerpts from Tom Lane's message of mar jul 10 10:56:50 -0400 2012:
> Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> writes:
> > 2012/7/10 Dimitri Fontaine <dimitri(at)2ndquadrant(dot)fr>:
> >> I'm not sure I can understand the difference between that and the use
> >> case for which you want to implement DO blocks with parameters.
>
> > this is similar to temporary functions - you need some temporary name
> > - it is insert to pg_proc, and you have to solve possible conflicts.
>
> What's to solve? Presumably the WITH function name would take
> precedence over anything in the catalogs, the same as WITH query names
> take precedence over actual tables.

Hm, would the newly defined function mask all regular functions with
that name? If not, a seemingly innocuous change in a query could mean
calling not the function defined in the WITH FUNCTION clause but another
one with the same name but different parameter count/types.

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