anchor.diff:       (assembler-error "SEGMENT expects a size."))
     (when *assign-blocks-to-segments?*
       (alet (assemble-expression ..x. :ensure? t)
  +      (& (zero? !)
  +         (assembler-error "SEGMENT size must be larger than 0."))
         (format t "Filling up segment of size ~a…~%" !)
         (assign-segment-block out !))))
   
  
positive.code: (defun assemble-parsed-expressions (out x)
    (adolist x
      (with-temporary *assembler-current-line* !
        (let-when b (car *sourceblock-stack*)
          (enqueue (sourceblock-exprs b) !))
        (adolist (.!)
          (? *disabled?*
             (? (equal ! '(directive end)) ; TODO end with block type
                (assemble-end nil))
             (assemble-and-dump out !))))))
  
  
negative.code:                                                  (>= (sourceblock-size a)
                                                       (sourceblock-size b))))))
  
  (defun assemble-parsed-files-0 (out-name dump-name x &key (unassigned-segment-blocks nil))
    (clear-labels)
    (= *pass* 0)
    (while (| *label-changed?*
  