o GENERALIZATION: Now it is possible to use any symbol for enclosing
  attribute values in RSP directives in addition to the current x='y'
  and x="y" ones, e.g. x=.y., x=|y|, and so on.  Furthermore, paired
  brackets may also be used, e.g. x={y}, x=[y], x=<y> and x=(y), and
  then also in matched replicated, e.g. x={{{y}}}.  Added several
  package system tests for this.