(vector-set! (block-content block) offset value)
         #t)))

;; Return the item at slot OFFSET.
(define-inlinable (block-ref content offset)
  (vector-ref content offset))

;; Return the offset of the next item in the hash bucket, after the one
;; at OFFSET.
(define-inlinable (block-hash-table-next-offset content size offset)
  (vector-ref content (+ size size offset)))

;; Save the offset of the next item in the hash bucket, after the one
;; at OFFSET.
(define-inlinable (block-hash-table-set-next-offset! content size offset
                                                     next-offset)
  (vector-set! content (+ size size offset) next-offset))

;; Returns the index of the last entry stored in CONTENT with
;; SIZE-modulo hash value KHASH.
(define-inlinable (block-hash-table-ref content size khash)
  (vector-ref content (+ size khash)))

(define-inlinable (block-hash-table-set! content size khash offset)
  (vector-set! content (+ size khash) offset))

;; Add hash table information for the item recently added at OFFSET,
;; with SIZE-modulo hash KHASH.
(define-inlinable (block-hash-table-add! content size khash offset)
  (block-hash-table-set-next-offset! content size offset
                                     (block-hash-table-ref content size khash))
  (block-hash-table-set! content size khash offset))

(define block-null
  ;; The null block.
  (make-block #f 0 0 #f))