monitoring the shell prompt

["Paolo M. Pumilia" <pol@xxxxxx>]

I would like to monitor the command line editor status and perform
some action as a change happen.
Since i use to switch often between vi-cmd and vi-ins modes, it would 
be useful to get the current vi mode displayed within the prompt 
As an example:
In command mode:  PROMPT='(@%m) %n - %% '
In insert mode:   PROMPT='(@%m) %n + %% '

Is it possible with the current version of zsh?

Thank you for your suggestions


Paolo Pumilia
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