RE: [External] : Re: Binding dired-up-directory to "b" by default

[Drew Adams]

Allow me to disagree a bit about this.

The directions/movements backward and forward (`b' and `f') don't really apply 
to navigating directories upward and downward, IMO.

And though "backward" (if thought of as "up") is generally unambiguous, 
"forward" (if thought of as "down") is not.  In general there's not just a 
single subdir.

`^' is fine, IMO, for moving up.  "Up" movement is unambiguous, in general.  
The ambiguous nature of "down" is maybe one reason there's no Dired key for 
such a movement (no "forward" key, if you like).

`f' (`dired-find-file') can do that (go down), but it doesn't necessarily even 
go to a Dired buffer.  

And the mnemonic for `f' is "file" (`dired-find-file').  And `F' is bound to 
`dired-do-find-marked-files' (in dired-x.el).  Let's not mix everything up - we 
should keep the mnemonic as "file", unambiguously, for Dired.

And `b' in a file buffer (not a Dired buffer) doesn't take you "back" (up) to a 
Dired listing of its directory.

When visiting a file buffer (after `f' or not), `dired-jump' (`C-x C-j') does 
take you "up" to its directory.  And in Dired it takes goes up a level and puts 
you on the line for the directory whose Dired buffer you came from.  IOW, we 
already have a key (`C-x C-j') for the notion of going up/"backward" to a 
directory from a file in it.
___

FWIW, we also have (from dired-aux.el) `dired-tree-up' and `dired-tree-down', 
bound by default to `C-M-u' and `C-M-d'.  

But those are for navigating within the same Dired buffer, between listings - 
main and subdirs at different levels.

There could be analogous up/down commands for moving to other Dired buffers 
above and below the current buffer's main directory, i.e., in separate buffers. 
 But there aren't any now.