Using bash in the default (emacs) mode I get the following behavior when I hit <ESC>.

$ echo hello
hello
$ hello  # I hit `<ESC>.` to insert this

Note there is no space before the word hello that is inserted when I hit <ESC>.

If I switch to vi mode and configure . I do get a leading space:

$ set -o vi
$ bind -m vi-command ".":yank-last-arg
$ echo hello
hello
$  hello  # I hit `<ESC>.` to insert this. Note the leading space.

Is there any way to configure bash/readline to avoid this leading space?