anchor.diff:    `(when (= +cl-success+ ,expr)
        ,@body))
   
  +#| Platform APIs |#
  +
   @export
   (defun get-platform-id ()
     (with-foreign-objects ((platforms 'cl-platform-id)
  
positive.code:                                                   errcode-ret)))
        (check-errcode-ret program 'cl-create-program-with-source errcode-ret))))
  
  @export
  (defun create-kernel (program kernel-name)
    (with-foreign-object (errcode-ret 'cl-int)
      (let ((kernel (cl-create-kernel program kernel-name errcode-ret)))
        (check-errcode-ret kernel 'cl-create-kernel errcode-ret))))
  
  @export
  (defun create-command-queue (context device properties)
  
negative.code:             (loop for n from 0 below num
                    collecting (mem-aref platforms 'cl-platform-id n))))))))
  
  #| Context APIs |#
  
  @export
  (defun create-context (properties
                         num-devices
  