Creating Records

Most commonly, records are created as a program runs, rather than being declared at compile time.

In Lisp, the function (cons x y ) always allocates a new record, then assigns its car and cdr pointers to be the specified values x and y.

Scheme (set! p (cons 3 lst))
Pascal new(p);
p^.car := 3;
p^.cdr := lst;
C++ cons *p = new cons;
p->car = 3;
p->cdr = lst;
Java Cons p = new Cons(3, lst);

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