Where does the magic 4 (C-u) come from?

Where does the magic 4 (C-u) come from?

[Deniz Dogan]

Hi

I just had a discussion on #emacs on freenode about the origin of the
behavior of C-u and the multiplying by 4. None of us could find any
information about why 4 was chosen and if this behavior has been
borrowed from somewhere else.

So I figured someone here ought to know... What is the origin of the magic 4?

-- 
Deniz Dogan

Re: Where does the magic 4 (C-u) come from?

[Thomas Lord]

On Fri, 2009-07-31 at 19:00 +0200, Deniz Dogan wrote:
> Hi
> 
> I just had a discussion on #emacs on freenode about the origin of the
> behavior of C-u and the multiplying by 4. None of us could find any
> information about why 4 was chosen and if this behavior has been
> borrowed from somewhere else.
> 
> So I figured someone here ought to know... What is the origin of the magic 4?


I don't know the historical answer but
4 is a natural choice if you count key
presses:

   x        1
   x x      2
   x x x    3
   C-u x    3

4 is the least, useful magic number (the
comma matters :-)

-t

Re: Where does the magic 4 (C-u) come from?

[Richard Stallman]

    > So I figured someone here ought to know... What is the origin of the magic 4?


    I don't know the historical answer but
    4 is a natural choice if you count key
    presses:

The quantities 4, 16 and 64 seem convenient for repeat counts of
motion commands.  A base larger than 4 would make them too far apart.