Re: Shouldn't jsonpath .string() Unwrap? - Mailing list pgsql-hackers

Hackers,

Most of the jsonpath methods auto-unwrap in lax mode:

david=# select jsonb_path_query('[-2,5]', '$.abs()');
 jsonb_path_query
------------------
 2
 5
(2 rows)

The obvious exceptions are size() and type(), which apply directly to arrays, so no need to unwrap:

david=# select jsonb_path_query('[-2,5]', '$.size()');
 jsonb_path_query
------------------
 2
(1 row)

david=# select jsonb_path_query('[-2,5]', '$.type()');
 jsonb_path_query
------------------
 "array"

But what about string()? Is there some reason it doesn’t unwrap?

david=# select jsonb_path_query('[-2,5]', '$.string()');
ERROR:  jsonpath item method .string() can only be applied to a bool, string, numeric, or datetime value

What I expect:

david=# select jsonb_path_query('[-2,5]', '$.string()');
 jsonb_path_query
—————————
 "2"
 "5"
(2 rows)

However, I do see a test[1] for this behavior, so maybe there’s a reason for it?