Clojurians Log v2

Just curious:

(for [elem [1 2 3]
      :let [elem+1 (inc elem)]]
  elem+1)
=> (2 3 4)

(for [:let [elems [2 3 4]]
      elem elems]
  elem)
Syntax error macroexpanding for at (core.clj:12:1).
Can't pop empty vector

I think there is a JIRA issue for it somewhere, but not very high priority, maybe even rejected. Just use a surrounding let in this case.

yep, this is what I am doing

Can anyone recommend a lib for managing datomic schema migrations with the client api library?

Does anybody have a better idea on how to write this?

I think it's just fine. Personally, I'd split the condition and the assoc into two lines.

Minor thing: I tend to use identical? on keywords, but = also works

Not cross-platform.

ClojureScript 1.10.773
cljs.user=> (def x :x)
#'cljs.user/x
cljs.user=> (identical? x :x)
false

I guess what I'm asking if it's ok to use cond-> to "simulate" something like if (cond) return f(a) else a

This is the entire function in case it helps

@p-himik Since this is the #clojure identical? is appropriate, in CLJS you use keyword-identical?, good to be aware

IMO that's exactly what it was created for. It supports a bit more, but that's OK use only a part of this potential.

@borkdude Sure.

FWIW I use cond-> in such scenarios all the time. :)

You should probably be using the clojure.spec.alpha/invalid? function though, the keyword may be an implementation detail

@borkdude makes sense, I'll change it

I'd use the shorter ::spec/invalid form of the keyword (and split up the lines as @p-himik suggested). Otherwise LGTM 👍