5.2 define-struct

(define-struct structid (fieldid ...))

The same as Intermediate’s define-struct, but defines an additional set of operations:

• make-structid : takes a number of arguments equal to the number of fields in the structure type, and creates a new instance of the structure type.

• set-structid-fieldid! : takes an instance of the structure and a value, and changes the instance’s field to the given value.