Bruce Momjian <bruce@momjian.us> writes:
> Does anyone know why the phrase distance "<3>" was changed from "at most
> three tokens away" to "exactly three tokens away"?
So that it would correctly support phraseto_tsquery's use of the operator
to represent omitted words (stopwords) in a phrase.
I think there's probably some use in also providing an operator that does
"at most this many tokens away", but Oleg/Teodor were evidently less
excited, because they didn't take the time to do it.
The thread where this change was discussed is
https://www.postgresql.org/message-id/flat/c19fcfec308e6ccd952cdde9e648b505%40mail.gmail.com
see particularly
https://www.postgresql.org/message-id/11252.1465422251%40sss.pgh.pa.us
regards, tom lane
