Re: What's missing in ELisp that makes people want to use cl-lib?

[Po Lu]

Dmitry Gutov <dmitry@gutov.dev> writes:

> Just to take this example, there are about 2 major bugs: 1) the list
> will come out reversed, 2) the code does XOR rather than subtraction.

Hmm, reading its doc string, I think a more illustrative name for
cl-set-difference would be cl-set-complement.  In this case, the second
loop can be removed.

If the order is significant (it seldom is), the list can be nreversed
afterwards.  Or alternatively a local variable can be maintained holding
the last cdr of the list, and insertion performed on that instead.