This looks like a case of "convergent evolution". Having the ability to do a :let in the middle of a cond feels like one of those things that *should* be in the core language, so if it's not in there, a bunch of people are naturally going to arrive at the same solution and make it happen in their own utility libraries. A bunch of us Clojure programmers from the early 1.0 days had been privately passing around and using a "cond that supports :let bindings" macro for years. The first time I saw the macro was in a blog post by Christophe Grand. I really hoped it would make it into Clojure proper -- other functional languages like Racket and F# support ways to bind local variables with "clearer, more linear code, that doesn't make a march for the right margin", as Howard Lewis Ship put it. But after several years had passed without any indication that CLJ-200 was ever going to be addressed, I eventually made the improved cond macro into a clojars library.
walmartlabs' cond-let addresses the most important thing (let), which is the critical piece of functionality that feels like the most natural, needed addition to the language. better-cond's :let syntax is identical. But as us old-school Clojurians passed around the "better cond" macro over the years, it grew in functionality. So in better-cond, I included the other little improvements that had accumulated over time, which I had found useful. So better-cond also supports :when, :when-let, and :do (and will soon have :when-some). :let is the only piece that I felt really belonged in the core language's cond, and if CLJ-200 had made it into the core language, I would have been content to just use Clojure's own cond. But once I realized I was going to need a library to achieve the much-needed :let inside of cond, I figured I might as well use that library to include the other convenient cond additions as well. So better-cond is a superset of cond-let's functionality, with support for :let plus a few bonuses. Use whichever one strikes your fancy. cond-let is perfect if all you care about is adding :let to your cond. If you want to experiment with some of the other features beyond :let, you could use better-cond and see what you think. Either way, I strongly encourage you to use one of these two libraries so you can start using :let inside your cond. I agree fully with Howard Lewis Ship that it results in clearer code. Try either library which supports this -- it will change your life! On Wed, Oct 3, 2018 at 5:05 PM Matching Socks <phill.w...@gmail.com> wrote: > Is this a refinement of Mark Engelberg's "better-cond", or an alternative > approach? > > I have not used better-cond myself, but it starts here: > https://dev.clojure.org/jira/browse/CLJ-200. > > -- > 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 > --- > You received this message because you are subscribed to the Google Groups > "Clojure" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- 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 --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
