custom ERC IRC /command

[Emanuel Berg]

How can I make a custom ERC IRC command,
e.g. /r which is unbound in
ERC Version 5.3 (GNU Emacs 24.4.1) - how can
I bind that to an Elisp defun?

In particular, I would like /r to repeat the
previous command, just like it does in zsh:

    $ echo "True sailing is dead"
    True sailing is dead
    $ r
    echo "True sailing is dead"
    True sailing is dead

Except it doesn't have to, eh, "echo" the
previous command input string, just have the
command executed :)

TIA

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underground experts united
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