On Fri, Oct 21, 2011 at 4:02 PM, Mark Engelberg <mark.engelb...@gmail.com>wrote:
> On Fri, Oct 21, 2011 at 12:41 PM, David Nolen <dnolen.li...@gmail.com> > wrote: > > Just because we have dynamic types does not give us the freedom to not > > consider them. > > Oh, I definitely considered the types when I wrote the function. It's > just that at the time I wrote it, I was confident the input would > already be seq-ified. nil, among its many purposes, is a key part of > the "seq interface", and testing for nil is how you are expected to > interact with seqs to determine emptiness. As my program grew, the > assumption that the input would definitely be a seq was invalidated. > This is exactly the inherent challenge of making evolving, > maintainable programs that Rich speaks of in his video. Testing for nil is not how you determine emptiness unless locally you are using next. (rest '()) -> () (next '()) -> nil David -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
