Lisp refactoring puzzle

[WJ]

Petter Gustad wrote:

> Xah Lee <xahlee at gmail.com> writes:
> 
> > it's funny, in all these supposedly modern high-level langs, they
> > don't provide even simple list manipulation functions such as union,
> > intersection, and the like. Not in perl, not in python, not in lisps.
> 
> In Common Lisp you have:
> 
> CL-USER> (union '(a b c) '(b c d))
> (A B C D)
> CL-USER> (intersection '(a b c) '(b c d))
> (C B)

The order was changed.

COBOL Lisp is always mindless.


* (union '(2 2 3 4) '(7 7 8 9))

(4 3 2 2 7 7 8 9)


The right way (MatzLisp):

[2,2,3,4] | [7,7,8,9]
    ==>[2, 3, 4, 7, 8, 9]