Adding eager null checking to Eagerly.zip and Eagerly.enumerate.
Adding eager null checking to Eagerly.comprehension.
Adding eager null checking to Eagerly.cartesianProduct.
Adding eager null checking to Eagerly.filter, Eagerly.reject and Eagerly.partition.
Adding eager null checking to Eagerly.first, Eagerly.last and Eagerly.rest variants.
Adding eager null checking to generators.
Adding eager null checking to iterators.