Re: To be a list or not

[Richard Stallman]

    Eh, yes but (sequencep '(prop . val)) also returns t at least in my 
    version of Emacs. But maybe this has been changed?

In a strict sense, that is not a sequence.  So ideally `sequencep'
should return nil.

However, making it return nil would require changing it from a
constant-time function to a linear-time function, and that seems like
a bad idea overall.