static L mapMethod(O[] l, fS methodName) {
  ret map(l, func(O o) { callOpt(o, methodName) });
}

static L mapMethod(Iterable c, fS methodName) {
  ret map(c, func(O o) { callOpt(o, methodName) });
}

static L mapMethod(S methodName, Iterable c) {
  ret mapMethod(c, methodName);
}

static L mapMethod(S methodName, Enumeration c) {
  ret mapMethod(methodName, enumerationToIterator(c));
}