realize

real eyes realize real lies

Lazy sequences aren't data. They can throw exceptions. They can fire missiles.

This lib can't help you if you're firing missiles, but it will realize all lazy sequences in a Clojure data structure, replacing them with {:realize.core/exception e} if they throw an exception.

(require '[realize.core :as [realize]])

(def e (Exception. "Boom!"))

(def danger-seq (map (fn [_] (throw e)) [1 2 3]))

(realize/realize {:foo danger-seq})
;; => {:foo {:realize.core/exception e}}

It also has a tool to check if your data structure threw any exceptions when being realized:

(require '[realize.core :as realize])

(def e (Exception. "Boom!"))

(realize/find-exceptions {:foo {:realize.core/exception e}})
;; => [{:exception e :path [:foo]}]

Install

Add [realize "2019-04-24"] to :dependencies in your project.clj.

Raison d'être

This lib was created so that Prone does not explode when given lazy-seqs that throw exceptions when realized.

Change log

From 1.1 to 2019-04-24

Realize now guards against infinite seqs, with a default limit of 10000 items in a seq.

The realize function takes an optional max-len argument to specify this limit.
Realize now reports errors that occur when find-exceptions is run. This might happen if you get an error like OutOfMemoryError or StackOverflowError when trying to find exceptions. Isn't this all a jolly good time?

From 1.0 to 1.1

Realize no longer walks into forms that cannot be recreated, like Datomic entities

Development

./bin/kaocha will run all tests.

./bin/kaocha --watch will run all the tests indefinitely. It sets up a watcher on the code files. If they change, only the relevant tests will be run again.

License

BSD-3-Clause, see LICENSE

cjohansen / realize