g.getRoots().retainAll(base.getRoots());
}
// mark the gap as closed
if (g.getOpenTemplateGaps().contains(gapname))
g.addClosedTemplateGap(gapname);
g.removeOpenTemplateGap(gapname);
if (g.getOpenAttributeGaps().contains(gapname))
g.addClosedAttributeGap(gapname);
g.removeOpenAttributeGap(gapname);
g.getGapTypeMap().remove(gapname);
// open again if the inserted value contains the gap