anchor.diff: -;;;;; Copyright (c) 2012,2014 Sven Michael Klose <pixel@copei.de>
  +; Copyright (c) 2012,2014–2015 Sven Michael Klose <pixel@copei.de>
   
   (defun cart-current ()      (!?   (session 'cart)      (phphash-alist !)))
   (defun cart-undos ()        (!?   (session 'cart-undo) (array-list !)))
  
positive.code:       (+! total (number (assoc-value 'price (cart-find-article i.)))))))
  
  (defun cart-items ()
    (template-list #'tpl-cart-item (filter [cart-find-article _.] (cart-current))))
  
  (defun cart-num-items ()
    (length (cart-current)))
  
negative.code:   (not (zero? (length (cart-current)))))
  
  (defmacro filter-cart (&rest body)
    `(= (cart-current) (@ [,@body] (cart-current))))
  
  (defun cart-redirect ()
    (action-redirect :update 'cart))
  