bug#19324: 25.0.50; add-function and nil

[Leo Liu]

On 2014-12-11 12:01 -0500, Stefan Monnier wrote:
> Indeed, I fixed the eldoc-documentation-function not to be nil.
>
>
>         Stefan

But :around are still broken. It promises to pass on ORIG but instead
passes a proxy. so the advice has no (public) way to tell missing
function. Do you have a fix for this? Otherwise we have to check and set
a dummy value to be safe, for example¹.

Leo

Footnotes: 
¹  
https://github.com/leoliu/ggtags/commit/115194cc27dd578b986aaaf0dc390bb57e9838b2