— Scheme Procedure: nil-car x
— C Function: scm_nil_car (x)

Return the car of x, but convert it to LISP nil if it is Scheme's end-of-list.

— Scheme Procedure: nil-cdr x
— C Function: scm_nil_cdr (x)

Return the cdr of x, but convert it to LISP nil if it is Scheme's end-of-list.

— Scheme Procedure: nil-cons x y
— C Function: scm_nil_cons (x, y)

Create a new cons cell with x as the car and y as the cdr, but convert y to Scheme's end-of-list if it is a Lisp nil.

— Scheme Procedure: nil-eq x y

Compare x and y and return Lisp's t if they are eq?, return Lisp's nil otherwise.

— Scheme Procedure: null x
— C Function: scm_null (x)

Return Lisp's t if x is nil in the LISP sense, return Lisp's nil otherwise.