RE: `append' vs. `nconc'

[Drew Adams]

> I have lots of ' and ` and instead of examining all
> those cases I think it is easier to look for the
> mutators, and see if ' or ` are used in their vicinity.
>
> I found this page: http://www.emacswiki.org/emacs/DestructiveOperations

Yes, just keep an eye out for the mutators; that's all.
And it's not about ' or `.  Whenever "destructive" functions
are involved, you need to keep an eye out more generally -
but specifically wherever the structures get mutated or used
(referenced).