I'm just skimming here, but if a jsonb_path type is being proposed,
perhaps it would be better not to have operators that take text or
text[] as second argument. We can provide that functionality with just
functions. For example, it will be confusing to have
jsonb 'some json value' - '{foo,bar}'
operate too differently from
jsonb 'some json value' - json_path '{foo,bar}'
And it will be a nasty regression to have 9.5 allow
jsonb 'some json value' - '{foo,bar}'
and then have 9.6 error out with "ambiguous operator" when the json_path
thing is added.
--
Álvaro Herrera http://www.2ndQuadrant.com/
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