Generic programs can't reliably use/manipulate documents via the DOM
github.com1 pointsby mrmr19930 comments
func evenNumberOfOnesAtStart(_ s : BitSequence) {
return (s.atIndex(0) == .zero ||
(s.atIndex(1) == .one &&
evenNumberOfOnes(BitSequence { s.atIndex($0 + 2) })))
}
evenNumberOfOnesAtStart == evenNumberOfOnesAtStart
will never terminate. (Disclaimer: I don't write Swift.)