orchestra

I strongly recommend that anyone using spec for validation should check out Orchestra, to instrument the functions and have them automatically validated on each and every call: https://github.com/jeaye/orchestra For my team, generators and parsing are basically useless with spec. We just don't use them. But describing the shape of data and instrumenting our functions, using defn-spec, to ensure that the data is correct as it flows through the system is exactly what we want and nothing I've seen in Clojure land does it like spec + Orchestra can. I think part of this may boil down to different types of testing. We primarily use functional testing, especially for our back-end, so we're starting from HTTP and hitting each endpoint as the client would. Then we ensure that the response is correct and any effects we wanted to happen did happen.

clojure.spec + orchestra for nicely integrated pre/post spec checking https://github.com/jeaye/orchestra

> I wondered why there’s a reduce in clojure.core but no fold? (It’s just a different arity of reduce that’s missing the initial state.) There is literally an arity of reduce which skips the initial state. Check out `(doc reduce)`. > No tuple type? Vectors are tuples. “What if one of the vectors is of a different length?” I gasped as I clutched my pearl monads. `s/tuple` is the answer to that question. > This ties into another concept that was new to me: applying a sequence of arguments to a function. You're not applying the sequence to the fn. This is "function application", so you're applying the fn to the sequence. In Clojure, you have some data, you apply a fn to it, then you have some transformed data. Rinse and repeat. Also, check out `(doc apply)`. > I’ve read/heard the Clojure designers encourage the use of namespaced keywords, bu

Yes, in my experience it does. In my projects I fdef all my functions and then turn on instrumentation (with the Orchestra[0] library, so that it also checks :ret specs). It helped me find several instances where I was incorrectly assuming that I would never get nil as an input. Couple it with Expound[1] to make reading the spec errors a bit easier, and you've got a much better story for handling nil in Clojure. [0]https://github.com/jeaye/orchestra [1]https://github.com/bhb/expound

> the return values of functions can be spec'd but they are not included in an assert test I agree this is a shortcoming, but that is why this library exists: https://github.com/jeaye/orchestra