Re: Collecting completion candidates from multiple files

[xenodasein]

>> I wondered about this also; is there built-in completion functionality that
>> can collect all words or symbols from existing buffers of the same mode, or
>> all existing buffers?
>>
>
> M-x find-library RET dabbrev RET
>
> This built-in library provides hooks like
> dabbrev-select-buffers-function.  Packages can customize it to return a
> custom list of buffers.  For example, a mode for a programming language
> that supports includes could implement a custom function that returns
> buffers created from parsing includes recursively (something like Vim's
> CTRL-P/CTRL-N, if I'm not mistaken).
>

AFAICT it doesn't have a way to connect to completion-at-point by default?
Maybe this would be a good feature to have.