How to call a bash-func from readline? && how to call rl-func from bash?

[L A Walsh]

How might one programatically call a bash
function from readline, and pass information from that function
back into readline?

Also, is it possible to define a readline
function, or only use predefined ones?


Ex:  On a keypress, I would like to be able to
redefine that key in ".bashrc" and have it call a
bash-function that could map the key to itself or
a sequence of keys based on the shell's current state.

How would someone do that?

Thanks!
-linda