Обсуждение: pgsql: Doc: clarify behavior of "anyrange" pseudo-type.

Doc: clarify behavior of "anyrange" pseudo-type.

I noticed that we completely failed to document the restriction
that an "anyrange" result type has to be inferred from an "anyrange"
input.  The docs also were less clear than they could be about the
relationship between "anyrange" and "anyarray".

It's been like this all along, so back-patch.

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9a9b87191a32fb97dbd9cad6d9a8a43a9fc31c16

Modified Files
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doc/src/sgml/extend.sgml | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)