Evolution

[James Wilkinson]

vailima wrote:
> 
> Just as you see it below, without using the period(s) in front of each
> data $tring, open Evolution and try to IMPORT the data as you see it,
> into Evolution ...
> 
>  Last Name
>  First Name
>  Title
>  Mailing Address
>  City
>  State
>  Zip Code
>  Country
>  Telephone 
>  FAX
> 
> The above data is in the ASCII format (also known as TeXT format)

OK: time to explain something.

ASCII is a way of encoding letters. But that's *all* the ASCII standard
does. It provides raw text without any meaning.

The example you gave implied a certain amount of meaning. It had data
fields (Last Name, Title, etc) and a structure. Just saying it's ASCII
doesn't mean that the file has to include that data, or that it has to
be laid out that way.

You're asking the computer to work out what each of the fields means by
looking at the context. Computers are notoriously bad at that: to do it
effectively, you'd probably have to implement a full, human-equivalent
AI.

What happens is that there are a whole load of ways of expressing
structure in ASCII files. The old standard for Unix mailers is the mbox
standard, closely related to RFC 2822 and its predecessors. You get
something like
  From <vailima at icontech.com>  Tue, 10 May 2005 11:27:16 -0400
  X-Original-To: ubuntu at westexe.demon.co.uk
  Delivered-To: ubuntu at westexe.demon.co.uk
...
  Subject: Re: Evolution 

  text of e-mail.

You can see that it's got a From line, a set of headers with a header
name, a colon, a space, and a value, a blank line, and then the e-mail
text. Then the whole thing repeats for each e-mail. That's the standard
mbox format. It normally only contains ASCII characters [1], but it's
not the only way of using ASCII.

If you go into a web browser and "view source" on a Web page, you'll see
another format that only contains ASCII characters, HTML[2]. Both mbox
and HTML files are ASCII. But a simple browser won't know what to do
with a mbox file, and although a mailer might be able to display HTML,
it won't be able to import sender and date from it.

A third example is the /etc/passwd file on your Unix box, which contains
certain user information. In ASCII format.

Analogy: English and Latin and Welsh and French all use the same Latin
alphabet (give or take an accent or so). I can read what the letters are
in a Welsh name. But I certainly couldn't tell you what it meant. If I
tried reading Hebrew or Chinese, I couldn't even tell you what the
letters were.

ASCII is rather like an alphabet for computers (*massive*
over-simplification). You still need a "language", a way of
understanding what's written in it.

Does that make things clearer?

James.

[1] For the purposes of this e-mail, I'm ignoring the existence of other
character sets...

[2] And XHTML, and XML...

-- 
E-mail address: james | "Minis on the other hand are just the wrong size. Too
@westexe.demon.co.uk  | small to work on directly and too large to put
                      | upside down on the workbench."
                      |     -- stevo at madcelt.org