Learning Clojure: Clojure's Reader is Unsafe

;; We've got a function, read-string, which can turn strings into data structures while doing no harm whatsoever,
;; and another function, read-string, which can turn strings into data structures while potentially causing arbitrary side effects depending on the content of the strings.

Not quite. There is no -spoon- read-string. As you pointed out, there's:

clojure.tools.reader.edn/read-string and
clojure.core/read-string

The namespace is part of the function's "identity" if you will. I'm sure you're aware of this, but not all of your visitors from HN will be.