default InvertibleCodec<T, G>
	toInvertibleCodec(final Function<? super T, Genotype<G>> encoder) {
		return InvertibleCodec.of(encoding(), decoder(), encoder);
	}
Converts this codec into an <em>invertible</em> codec, by using the given
{@code encoder} (inversion) function.

@param encoder the (inverse) encoder function
@return a new invertible codec
@throws NullPointerException if the given {@code encoder} is {@code null}
jenetics/src/main/java/io/jenetics/engine/Codec.java