Assignments
^^^^^^^^^^^

.. crowbar:element:: AssignmentStatement <- AssignmentBody ';'
                     AssignmentBody <- DirectAssignmentBody / UpdateAssignmentBody / CrementAssignmentBody

.. crowbar:element:: DirectAssignmentBody <- Expression '=' Expression

    .. todo:: define direct assignment

.. crowbar:element:: UpdateAssignmentBody <- Expression ('+=' / '-=' / '*=' / '/=' / '%=' / '&=' / '^=' / '|=') Expression

.. crowbar:element:: CrementAssignmentBody <- Expression ('++' / '--')

.. todo:: define other assignments relative to direct