Re: jsonpath

Hi.

Attached patch enables throwing of errors in jsonb_path_match() in its 
non-silent mode when the jsonpath expression failed to return a singleton
boolean.  Previously, NULL was always returned, and it seemed to be 
inconsistent with the behavior of other functions, in which structural and 
other errors were not suppressed in non-silent mode.


We also think that jsonb_path_match() needs to be renamed, because its 
current name is confusing to many users.  "Match" name is more suitable for
jsonpath-based pattern matching like that (maybe we'll implement it later):
 jsonb_path_match(   '{ "a": 1, "b": 2,    "c": "str" }',   '{ "a": 1, "b": @ > 1, * : @.type == "string" }' )

Below are some possible name variants:
 jsonb_path_predicate() (original name)

  jsonb_path_pred() jsonb_path_test() jsonb_path_check()

 jsonb_path_bool()

-- 
Nikita Glukhov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company