Clojurians Log v2

this is so dang cool

Very nice, Andrei! Is the interpreter state a persistent data structure (value) that can be copied? How high are boundary conversion costs of types between Lua and Clojure?

oh wait, this is purely in clojure, no ffi. i'm even more surprised and impressed. how's performance?

Hi @whilo! You can check sections Persistent State — Globals Across Runs and Multithreading at https://github.com/galatyn/clua for some details. In short: • sandbox is a regular Clojure structure so you can do whatever you want. • Compiled script is also data structure and potentially can be used over threads or whatever, but at the moment it is not available at high level API. Easy to expose if needed. • Script state (vars, stack etc) should not be shared between threads. A small example:

;; Create the sandbox once, reuse across threads
(def sb (stdlib/sandbox-standard))

(future (lua/execute sb "return compute()"))
(future (lua/execute sb "return compute()"))

@nbtheduke Hi there 🙂 Since it is pure interpreter, it is not as performant as Clojure code, but as for scripting engine I would say it is fast enough 🙂 Just as example, Lua script running by interpreter:

(time (count (lua/execute "
  local t = {}
  for i = 1, 1000000 do t[i] = i * i end
  return t
")))
"Elapsed time: 4835.855417 msecs"

(time (count (reduce
               (fn [m i]
                 (assoc m i (* i i)))
               {}
               (range 1000000))))
"Elapsed time: 652.967209 msecs"