Bash and its exclamation mark command, preview actual command before executing it

It doesn't highlight the selection, but otherwise I think it works fine.

Try running

$ bind -p | grep copy-region-as-kill

to make sure that C-x C-r actually worked.

It should say:

"\ew": copy-region-as-kill

After that, it should work fine.

Example:

$ abc<C-Spc><C-a><M-w> def <C-y>

gives me

$ abc def abc

If you ever want to know where mark is, just do C-x C-x.

Example:

$ <C-Spc>abc<C-x><C-x>

will put the cursor back to where you set mark (the start of the line).

Also, I don't think you need to add the set-mark binding. I didn't.

$ bind -p | grep set-mark
"\C-@": set-mark
"\e ": set-mark
# vi-set-mark (not bound)

(note that most terminals send C-@ when C-Spc is pressed. I assume yours does too.)

If all this fails:

• does Ctrl+Space work in emacs -nw on the same terminal?
• do other Alt/Meta shortcuts work in bash?

Bash has a precommand hook. Sort of.

preexec () {
  clear
}
preexec_invoke_exec () {
    [ -n "$COMP_LINE" ] && return                     # do nothing if completing
    [ "$BASH_COMMAND" = "$PROMPT_COMMAND" ] && return # don't cause a preexec for $PROMPT_COMMAND
    local this_command=`history 1 | sed -e "s/^[ ]*[0-9]*[ ]*//g"`; # obtain the command from the history, removing the history number at the beginning
    preexec "$this_command"
}
trap 'preexec_invoke_exec' DEBUG