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Re: building "path expressions"

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On 01/23/2014 04:12 PM, Stefan Ram wrote:
> Jeff Higgins <jeff@invalid.invalid> writes:
>> Do you have an example using some real world names to help me understand?
>
>    In Android programming, they use names like
>
> R.layout.main
>
>    . »R« is a public final class. »layout« is a nested public static final
>    class, but when using »R.layout.main«, one cannot know this; »layout«
>    could be a field as well (usually, one also does not need to know this,
>    so it's just fine as it is. I am not complaining.).
>
>    The meanings are as follows:
>
> R               the space of automatically-defined constants
> R.layout        the subspace of layout-related constants
> R.layout.main   a constant for the layout of the main activity
>
>    The name »R.layout.main« is the »user interface«. It can be
>    implemented with either a nested static class »layout« or a
>    field »layout«. It might be even possible to change this
>    later without breaking too many clients.
>
>    Yes, the class »layout« officially is written with a lower-case »l«.
>    These Google folks, they do not have any respect.
>
   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.

   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:

package a.b.c;
class G { int h = 8; }
class F { G g = new G(); }
class d { static class e { static F f = new F(); }}
public final class Main
{ public static void main( String[] args )
   { java.lang.System.out.println( a.b.c.d.e.f.g.h );  }}

I guess I'm being dense today.
I can't relate your example to your OP.
Do Javadocs help?

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Re: building "path expressions" Jeff Higgins <jeff@invalid.invalid> - 2014-01-23 15:27 -0500
  Re: building "path expressions" Jeff Higgins <jeff@invalid.invalid> - 2014-01-23 16:11 -0500
  Re: building "path expressions" Jeff Higgins <jeff@invalid.invalid> - 2014-01-23 16:52 -0500
    Re: building "path expressions" Jeff Higgins <jeff@invalid.invalid> - 2014-01-23 17:29 -0500
      Re: building "path expressions" markspace <markspace@nospam.nospam> - 2014-01-23 15:33 -0800

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