public static <T> EphemeralConst<T> of(final Supplier<T> supplier) {
		return new EphemeralConst<>(null, supplier);
	}
Create a new ephemeral constant with the given value {@code supplier}.
For every newly created operation tree, a new constant value is chosen
for this terminal operation. The value is then kept constant for this tree.

@param supplier the value supplier
@param <T> the constant type
@return a new ephemeral constant
@throws NullPointerException if the {@code supplier} is {@code null}
jenetics.prog/src/main/java/io/jenetics/prog/op/EphemeralConst.java