watch this: $ sbcl This is SBCL 2.4.8, an implementation of ANSI Common Lisp. * (setf z #C(1 2)) #C(1 2) * (* z (conjugate z)) 5 * (sqrt (* z (co

watch this: $ sbcl This is SBCL 2.4.8, an implementation of ANSI Common Lisp. * (setf z #C(1 2)) #C(1 2) * (* z (conjugate z)) 5 * (sqrt (* z (conjugate z))) 2.236068 * (abs z) 2.236068