Lua vs ClojureScript

One of the best features of Lua is its very well designed C API. This is very useful if you have an existing C library you need to integrate with Lua or quickly get a Lua script running on the C side of the game.

Finally Lua plays so nice with C that if you need to optimise for speed you can re-write it in C a lot easier than other languages.

The official Lua documentation is very helpful and thorough. There are also a large number of online resources or books with lots of helpful information for beginners and advanced users alike.

Lua can be built on any platform with a ANSI C compiler.

Other than that, Lua is extremely small. For example, the tarball for Lua 5.2.1 is only 245K compressed and 960K uncompressed (including documentation).

When built on Linux, the Lua interpreter built with the standard libraries takes 182K and the Lua library takes 243K.

The small size and the ability to build with a C compiler make Lua an extremely portable language that can run on a lot of different systems and computers.

Easy to learn.

Lua's performance compares very well to other languages, If performance needs to be further improved you can:

1. Implement critical parts in C
2. Use the LuaJIT compiler. The LuaJIT compiler is a drop in replacement for the stock compiler and provides significant performance improvements. From the overview page:

LuaJIT speeds can rival code written in C.

Many different game engines (e.g. Elder Scrolls series, ToME) use Lua for scripting, and it's runtime is designed for embedded use.

The Lua syntax is modeled from Modula, a language known for being a fantastic introduction to programming.

The Lua syntax also has the following key characteristics:

• Semicolon as a statement separator is optional (mostly used to resolve ambiguous cases as in a = f; (g).x(a)).
• Syntactic sugar for function calls (f'string', f"string", f[[string]], and f{table}) and method calls (obj:m()).

Due to the growing popularity, Lua has a rather large and helpful community surrounding it.

Figwheel builds your ClojureScript code and hot loads it into the browser as you are coding! Every time you save your ClojureScript source file, the changes are sent to the browser so that you can see the effects of modifying your code in real time.

Lispness makes ClojureScript trivial to comprehend after an initial learning overhead.

Clojure and ClojureScript are designed to be able to interact with their host. So the language by design makes it is easy to use existing JS libraries.

Google's Closure Library converts regular JavaScript into a highly optimized form - including dead code analysis/elimination. It can even remove pieces of unused code from 3rd party libraries (eg, if you import jQuery but only use one function, Google Closure includes only that piece).

Clojure is also able to run web servers, so one can reap similar benefits to NodeJS in terms of sharing code between client and server.

Both Leiningen and Boot are great build tools that manage code dependencies and deployment.

ClojureScript has superb wrappers around React.js (see Reagent) that make building single-page apps a breeze. With figwheel, it's a web dev experience unlike any other -- hotloaded code, repl interaction, and instantly reflected changes make good development fun and fast. You can add things like Garden to make CSS-writing part of the same holistic experience and suddenly all development is a pleasant, smooth process.

From the creator of Clojure:
Spec is a new core library (Clojure 1.9 and Clojurescript) to support data and function specifications in Clojure.
Writing a spec should enable automatic: Validation, Error reporting, Destructuring, Instrumentation, Test-data generation and Generative test generation.