Excerpts from Ruthard Baudach's message of 2014-09-14 20:07:27 +0200:
> Dear list,
> 
> I'd like to activate the signature hook. I have got two email addresses
> that I put for both private colloquial and privat formal use as well as occasional
> professional use.
> 
> Therefor I have to base the signature of the mail currently composed on
> the content of the mail and not on the From: header.
> 
> But how can I write an interactive hook?
> 
> puts puts a string in the status line, but gets crashes the hook
> 
> I'd like to have a prompt:
> Choose signature [1* 2 3 4]
> and to be able to enter the appropriate key to choose
> 
> Yours, Ruthard

Hello,

I'm afraid you're not going to be able to do this with a hook; you're
gonna have to change the core of sup.

At a quick glance, the most straightforward thing for you to do is to
play with the selectors in edit_message_mode; these are the choices you
get at the top of the mode. See @account_selector and @crypto_selector
in edit_message_mode.initialize.

What you can do is add a @signature_selector, displaying all possible
signatures associated to your account and allowing you to choose the one
you want. You'll certainly have to then re-call
edit_message_mode.sig_lines depending on the choice you make, and maybe
other parts in edit_message_mode too.

From a config point of view, here's what you'd have to change:

- add a "signatures" setting, with a folder that has a list of files;
  each file would contain a different signature and the selector I
  mentioned earlier will offer a choice between file names:

  $ head ~/.config/sup/signatures/*
  ==> work <==
  Serious Business Inc.

  ==> family <==
  Matthieu Rakotojaona

  ==> friends <==
  rakoo

  This particular setting would give me a choice between "work",
  "family" and "friends" when editing a message

- keep a possibilty to set a "signature" in the account for backwards
  compatibility (and people with only 1 signature)

Good luck !

(Also random idea, slightly related to the subject: if neither
signature nor signatures is specified in the account, put a default
signature that contains the name of the user as specified in the account
? That default sounds reasonable enough to me)

-- 
Matthieu Rakotojaona