Clojure wat

wat.clj

user=> (def bs '[a 1 b 2])
#'user/bs
user=> (type bs)
clojure.lang.PersistentVector
user=> (vector? bs)
true
user=> (let bs (+ a b))
java.lang.IllegalArgumentException: let requires a vector for its binding (NO_SOURCE_FILE:0)

Yeah, and for someone "in the know" it is trivial to demonstrate what happened:

user=> (defmacro foo [thingy] (type thingy))
#'user/foo
user=> (foo bs)
clojure.lang.Symbol

But this sort of thing can be so bewildering to fresh clojure programmers, and the error is effectively telling you to do exactly what you did, as far as a naive inspection might discover.

It makes me feel bad for the newbies :)