Message-Id: <m0qRCcb-0003pLC@acid.base.com>
From: gordoni@home.base.com (Gordon Irlam)
Subject: Re: URL revision
To: connolly@hal.com (Daniel W. Connolly)
Date: Thu, 21 Jul 1994 21:54:08 -0700 (PDT)
In-Reply-To: <9407210507.AA10669@ulua.hal.com> from "Daniel W. Connolly" at Jul 21, 94 00:07:55 am
> In message <94Jul20.170935pdt.2761@golden.parc.xerox.com>, Larry Masinter write
>
> >12. The URL: prefix requirement is still controversial, in that there
> >are still strong opinions about it. If we were voting (which we were
> >not) the votes would have it moved. I'm reluctant to touch this
> >without a stronger mandate.
>
> Hello? Did I miss it again? WHAT IS THE ARGUMENT IN FAVOR OF THIS?
1) Useability.
If possible we should try and make it easy for anything we design
to be used by niave users.
If everything used in the same fashion has the same prefix it makes
it much easier for niave users to recognise, and know what to
do with it.
[Niave users are very important. There are a lot of them! If we
design a system for niave users, experts can still use it -- they
just have to enter a few more keystrokes. If we design it for
experts, niave users either can't use it, and get very frustrated.
A lot of the success of the Web is a result of the fact that my
Grandmother can use it; people can make use of the Internet without
having to know the difference between an ftp address and an email
address.]
I'm not sure if the chosen prefix should be common just to URL's,
or to URI's too. It probably depends on whether we intend for it
to be possible to enter a URL where a URN is expected. If so
a more user friendly prefix like "WWW:" or "Web:" might also make
sense.
Note that the phone number name space did not specify a common
prefix, but because it is necessary for people to be able to
recognize phone numbers from other numbers, by convention people
have adopted a de facto prefix, Ph.
2) Namespace design.
If a name space has a common prefix it makes it easier to integrate
it with other name spaces. It will usually be possible to construct
a new name space as the union of two name spaces, without having
to make either one of the name spaces sub-ordinate to the other.
Eg. it might be nice to be able to construct the union of the URL
name space and a file system name space. Then I could call open()
with either a file name or a URN, and obtain a handle on the
relevant object. If neither name space uses a prefix, the chance
of a collision is much higher, and you might not be able to determine
from which name space a object comes just by looking at its name.
Gordon.