Java and Scripting languages

javaluascripting

I am making some kind of sandbox-engine, the end-users are able to make scripts to make their world dynamic etc, currently I am only looking at LuaJava because I have quitte some experience with Lua and find it a very readable/easy language. But I also understand that it might be a bad idea to choose only based on personal preference, after all Lua is meant to be embedded into C so performance wont be the best I imagine.

But after a look at some of alternatives (Groovy, Clojure) I find the syntax just unreadable/too abstract, Lua was my first programming experience and even that was quite hard to 'get' at first, I'm afraid these languages would just have scared the crap out of me and I would never have looked at scripting again.

Are there scripting languages that can be embedded in Java that compete with Lua on simplicity?

Edit
My problem with JavaScript, JPython is all the braces etc, as a starting user symbols tend to look 'hard'. Also for python there is the concept of Object's that the user needs to comprehend and isn't that useful in this case.

func = function(arg)
   print(arg)
end

Is so simple…

Best Answer

I think JavaScript is very simple, and it can be embedded in Java quite easily via Rhino. Scripts can be both pre-compiled, or compiled on-the-fly via the javax.script classes, which are used to connect to script engines for the Java platform (of which Rhino is one).

If you like Lua, though, there's a Lua for Java project called — *cough* — Kahlua. They list "Fast runtime of the most common operations" as one of their goals.

Edit: Re your edit, I'm not immediately seeing why this:

func = function(arg)
   print(arg)
end

is substantially easier to understand than this:

func = function(arg) {
   print(arg);
};

...which is the literal translation from Lua to JavaScript, pre-supposing a function called print exists on your platform. I would normally write that like this instead:

function func(arg) {
   print(arg);
}

...but the other way is fine for most purposes.

But you should use what you're comfortable with.

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