Re: Feature request for Bash

[Bob Proulx]

Ryan Campbell Cunningham wrote:
>     I would like to request that Bash delete the character
>     immediately preceding a '#', provided the '#'
> ...
>     (The request was inspired by an article in the seventh
>     edition of the UNIX Programmer's Manual. This feature
>     is not required by POSIX, but came from the traditional
>     Bourne shell.)

This isn't a feature of the shell but of the tty driver.  It still
exists.  It is still possible to use it today exactly as it was used
in Unix V7.

  $ stty -a | grep --color erase
  intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;

  $ stty erase '#'

  $ stty -a | grep --color erase
  intr = ^C; quit = ^\; erase = #; kill = ^U; eof = ^D; eol = <undef>;

Feel free to try it.

You can also customize the behavior of your bash libreadline by
setting the backward-delete-char key binding.  Place the following in
your $HOME/.inputrc file for example.

  "#" backward-delete-char

>     I would like to request that Bash delete the character
>     immediately preceding a '#', provided the '#'
> 
>        * does not begin a new word,
>        * is not included in any quoted string or variable,
>        * is not preceded by a '\', and
>        * is only found in an interactive command line (not
>          in a script* or Bash initialization argument).
> 
>     An exception: If the character immediately preceding
>     is also a '#', Bash should skip backward to the previous
>     non-'#' character and delete as much characters as the
>     number of consecutive '#' characters after them in the
>     same word.

Oh my, isn't that a complicated set of rules!  That is bound to cause
trouble.  Not good.  Plus that isn't how it worked in V7 days.

Bob