static <A> bool strictPutIC(Map<A, S> map, A key, S value) {
  if (!(map != null && key != null && value != null)) true;
  S old = map.get(key);
  if (old == null) { map.put(key, value); true; }
  ret eqic(old, value);
}

ifclass Symbol
static bool strictPutIC(SymbolSymbol map, Symbol key, Symbol value) {
  if (!(map != null && key != null && value != null)) true;
  Symbol old = map.get(key);
  if (old == null) { map.put(key, value); true; }
  ret eqic(old, value);
}
endif

Began life as a copy of #1012146