Re: factorial function/phase out postfix operators?

So I've finished up applying 0001 and started to look at 0002
... and I find the terminology you've chosen to be just really
opaque and confusing. "aliastype" being "implicit" or "explicit"
is not going to make any sense to anyone until they read the
manual, and it probably still won't make sense after that.

In the first place, the terminology we use for these things
is usually "column label", not "alias"; see e.g.
https://www.postgresql.org/docs/devel/queries-select-lists.html#QUERIES-COLUMN-LABELS
Likewise, gram.y itself refers to the construct as a ColLabel.
Aliases are things that appear in the FROM clause.

In the second place, "implicit" vs "explicit" just doesn't make
any sense to me. You could maybe say that the AS is implicit
when you omit it, but the column label is surely not implicit;
it's right there where you wrote it.

I confess to not having paid very close attention to this thread
lately, but the last I'd noticed the terminology proposed for
internal use was "bare column label", which I think is much better.
As for what to expose in pg_get_keywords, I think something like
"label_requires_as bool" would be immediately understandable.
If you really want it to be an enum sort of thing, maybe the output
column title could be "collabel" with values "bare" or "requires_AS".

So I'm thinking about making these changes in gram.y:

ImplicitAlias -> BareColLabel
implicit_alias_keyword -> bare_label_keyword

and corresponding terminology changes elsewhere.

Thoughts?

regards, tom lane