code: public static <T> ToDoubleFunction<T> toDoubleFunction(CheckedToDoubleFunction<T> function) {
          return toDoubleFunction(function, THROWABLE_TO_RUNTIME_EXCEPTION);
      }
docs: Wrap a {@link CheckedToDoubleFunction} in a {@link ToDoubleFunction}.
  <p>
  Example:
  <code><pre>
  map.computeIfAbsent("key", Unchecked.toDoubleFunction(k -> {
  if (k.length() > 10)
  throw new Exception("Only short strings allowed");
  
  return 42.0;
  }));
  </pre></code>