// returns a list of var mappings
static L<Map<ISearchVar, O>> xsearch(L<ISearchVar> vars, Class c, O... params) {
  for (ISearchVar v : vars) v.set(null); // reset vars
  params = expandParams(c, params);
  new L<Map<ISearchVar, O>> l;
  for (A concept : list(c))
    if (searchConcept_checkParams(concept, params)) {
      // Success. Record var mapping
      l.add(xsearch_makeVarMapping(vars));
      // Reset vars
      for (ISearchVar v : vars) v.set(null); // reset vars
    }
  ret l;
}

static Map<ISearchVar, O> xsearch_makeVarMapping(L<ISearchVar> vars) {
  new HashMap<ISearchVar, O> map;
  for (ISearchVar v : vars) {
    O o = v.get();
    if (o != null)
      map.put(v, o);
  }
  ret map;
}