Am Fri, 3 Jul 2015 07:15:20 +0100 schrieb Joseph Wright:

> Hmm, suggests an idea. Would a new property .reset: or similar work
> here? Logic:
> 
>  - Order does not matter: just accumulate whatever is applied.

Order will naturally still matter if one declare mutually exclusive
properties. So some clarification about which property overwrites
another would be fine anyway.

>  - key .reset: zaps *everything* (could also be called key .delete:
>    or key .clear).

Looking at the various properties I see the following distinct
properties that one would perhaps want to reset 

.value_forbidden:
.value_required:
.groups:n
.default:xx
"known status"
"action" (all the rest without .initial:, which you can't undo)

.default:xx, groups:n and "action" don't need imho some special
care:

- .default:X can imho be reset with .default:n= {}.
- .groups:n can imho be reset with  .groups:n = {}.
-  the action can be reset by setting a new action.


Missing is ".value_not_required:" and ".value_not_forbidden:". 

Missing is an explicit ".unknown:", which would e.g. allow to remove
choices from a key. An accompayning ".known:" which reactivates the
key would be interesting too. (I don't know if the code allows
this). 

An additional ".delete:" which clears a key completly would be good
too. 



-- 
Ulrike Fischer 
http://www.troubleshooting-tex.de/