Bug#212034: Debian Perl Policy manual uses "dependency" backwards

["Daniel B." <dsb@smart.net>]

Chris Waters wrote:
> 
> On Mon, Sep 22, 2003 at 08:57:16PM -0400, Daniel B. wrote:
> 
> > Since the other package is not dependent on perl, then by your own
> > dictionary's definition, the other package is not a dependency of
> > perl.  (Any divergence between us yet?)
> 
> This is your point of error.  The dependency belongs to perl, that's
> why it's a dependency OF perl's.  

Which sense of dependency do you meant, 1) a relationship of dependence, 
or 2) a thing involved in such a relationship?


(Recall the dictionary definition:

  dependency ...:
    1. Dependence. 
    2. Something dependent or subordinate. 
    ...
)

A "dependency of perl's" in sense 1 is a relationship of dependence 
in which perl is involved (e.g., "One dependency of perl is that it 
requires libc").  We probably don't disagree here.

A "dependency of perl's" in sense 2 is "something that is dependent" 
(on something else) and that belongs to perl in some sense.  So which
something is it?:
1. Perl depends on its prerequisites, so perl is dependent, but perl
   isn't a dependency of itself.
2. A package that perl depends on does not depend on perl, so it is 
   not dependent and it is not subordinate, so (per the dictionary) 
   it is not a dependency of perl.
3. A package that depends on perl does depend on perl (duh!), so it
   is dependent, so (per the dictionary) it is a dependency of perl.



> If the other package had the
> dependency, then it would be a dependency ON perl, not "of".

No.  A "dependency on perl" is not a package involved in a dependence
relationship.  (The package _has_ a dependency on perl but it _is_ not
a dependency on perl.)

Per sense 1 above, a "dependency on perl" is a "dependence on perl."

Per this:

  dependence
    ...
    2.a.Subordination to someone or something
          needed or greatly desired. 
      b. ...reliance. 

a "dependence on perl" is a "reliance on perl." 

So, clearly, a "dependency ON perl" cannot refer to a package.  It
refers to some package's dependence on perl.



> I am dependent on coffee, therefore coffee is a dependency of mine.

Not that I can swear that I've never heard the usage you claim, but do 
you have a definition from a (professional) dictionary that documents 
that usage?

(That one can't say, "Guam is dependent on the U.S., therefore the U.S.
is a dependency of Guam's" (or "of Guam").)

I think your example is really saying "a dependence or reliance on 
coffee is a dependency of mine."  


However, if it really is valid for "dependency of X" to mean something 
on which X depends (coffee as a dependency of yours) and to mean
something that depends on X (Guam as a dependency of the U.S.), then
obviously "dependency" (in sense 2) should not be used to refer to
_either_ depending packages or depended-on packages.



Daniel
-- 
Daniel Barclay
dsb@smart.net