public static <T> Var<T> of(final String name) {
		return new Var<>(name, 0);
	}
Create a new variable with the given {@code name}. The projection index
is set to zero. Always prefer to create new variables with
{@link #of(String, int)}, especially when you define your terminal
operation for your GP problem.

@see #parse(String)

@param name the variable name. Used when printing the operation tree
       (program)
@param <T> the variable type
@return a new variable with the given {@code name} and projection index
        zero
@throws IllegalArgumentException if the given {@code name} is not a valid
        Java identifier
@throws NullPointerException if the given variable {@code name} is
        {@code null}
jenetics.prog/src/main/java/io/jenetics/prog/op/Var.java