Re: add some errhint for regexp* functions.

jian he <jian(dot)universality(at)gmail(dot)com> writes:
> Some of the regexp* function error messages seem not very helpful, I think.
> like:
> ereport(ERROR,
> errcode(ERRCODE_INVALID_PARAMETER_VALUE),
> errmsg("invalid value for parameter \"%s\": %d",
> "start", start));

> so I added a errhint, errhint would be better than refactoring existing errmsg.
> for the above example, I've add:

> + errhint("\"%s\" must be an integer value greater than zero", "start")));

There are probably hundreds of other places where the ereport
doesn't provide such detail, and I don't see that this adds
much. If you don't understand why a negative value isn't OK,
you still need to go RTFM.

(This message doesn't follow our style guidelines, either.)

regards, tom lane