I'd suggest avoiding macros until you absolutely know that you need them. Usually they aren't necessary.
Prefer writing pure functions (without side effects) - these are easier to reason about, easier to test, simpler to write correctly and easier to plug together / compose via higher order functions. For example, in your endpoint example I would probably just use three functions: - a pure "add endpoint metadata to an endpoint map" function - an impure "update endpoints" function that updates endpoints using an endpoint map - a function that calls both of the above to declare and launch a new endpoint There might be a few other helper functions as well but hopefully you get the idea. On Thursday, 8 August 2013 03:19:15 UTC+1, Jace Bennett wrote: > > Thanks to the community for a wondrous programming environment. I > discovered SICP last year, and fell in love with the idea of lisp. But I've > come to a point where I think I need practice on moderately sized projects > before more reading will help. > > When starting on almost any moderately scoped effort, I quickly run into a > class of problems which I think may be a fit for macros, but I want to > understand what is the idiomatic way to approach them in clojure. > > Most of my professional experience is in .NET, and that is probably > coloring my thought patterns a bit. In that context, I often use reflection > scans and type metadata to configure infrastructural bits and dry things > up. Instead of having to explicitly register components in the more dynamic > areas of my app, I use conventions to select components to register from > the metadata I have about my code. > > I can imagine using macros in clojure to accumulate metadata about my > declarations so that I can query them at runtime. For example, maybe a > "defendpoint" macro that sets up a handler AND adds it to the routing table > (or more directly an "endpoint map" which I then use to make routing > decisions among other things). > > Admittedly, something about the sound of the phrase "it's just data" tells > me I'm sniffin up the wrong tree here. But I don't know how to turn that > nagging feeling into working code. > > Is this a reasonable use of the macro? What about doing the registration > at macro-expansion time vs emitting runtime code to do it? How should one > approach the problems space otherwise? > > Thanks for your time. > -- -- 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/groups/opt_out.
