public static <T> EphemeralConst<T> of(
		final String name,
		final Supplier<T> supplier
	) {
		return new EphemeralConst<>(requireNonNull(name), supplier);
	}
Create a new ephemeral constant with the given {@code name} and 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 name the name of the ephemeral constant
@param supplier the value supplier
@param <T> the constant type
@return a new ephemeral constant
@throws NullPointerException if one of the arguments is {@code null}
jenetics.prog/src/main/java/io/jenetics/prog/op/EphemeralConst.java