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From: Jeff Higgins <jeff@invalid.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: building "path expressions"
Date: Thu, 23 Jan 2014 17:29:53 -0500
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On 01/23/2014 05:04 PM, Stefan Ram wrote:
> Jeff Higgins <jeff@invalid.invalid> writes:
>> I can't relate your example to your OP.
>
>    The OP had the »path expression« (more official lingo:
>    »qualified name«) »a.b.c.d.e.f.g.h« while the follow up had
>    the »path expression« »R.layout.main«.
>
>    For another example: in Bioinformatics, one might want the
>    information about humans in a library to be accessible under
>
> Animalia.Chordata.Mammalia.Primates.Hominidae.Hominini.Homo.Homo_sapiens
>
>    , and one still can be free to decide what part of this path
>    is a package, class or field.
>

That's a fairly spare requirements document.

   When creating an interface for a library, sometimes one wants the user
   to see nesting in a »path expression«, like for example »a.b.c.d.e.f.g.h«
   to convey the idea that h is a part of g, which is a part of f, and 
so on.

a.b.c.e.f.g.h
The nesting is clear except as Eric Sosman noted, not in the package name.

   I think it is funny that one can use either package names /or/ nested
   classes /or/ fields to implement such a path, without this choice being
   visible in the »path expression«. For example, one posssibility to
   implement a »path expression« »a.b.c.d.e.f.g.h« might be:

Why would one want type information visible in your "path expression".