Dylan vs. Lua vs. QML vs. Racket Comparison Chart

Lua is a powerful, efficient, lightweight, embeddable scripting language. It supports procedural programming, object-oriented programming, functional programming, data-driven programming, and data description. Lua combines simple procedural syntax with powerful data description constructs based on associative arrays and extensible semantics. Lua is dynamically typed, runs by interpreting bytecode with a register-based virtual machine, and has automatic memory management with incremental garbage collection, making it ideal for configuration, scripting, and rapid prototyping. Lua has a deserved reputation for performance. To claim to be "as fast as Lua" is an aspiration of other scripting languages. Several benchmarks show Lua as the fastest language in the realm of interpreted scripting languages. Lua is fast not only in fine-tuned benchmark programs, but in real life too. Substantial fractions of large applications have been written in Lua.

Racket is a general-purpose, multi-paradigm programming language that serves as a modern dialect of Lisp and a descendant of Scheme. It is designed as a platform for programming language design and implementation, enabling developers to create new domain-specific and general-purpose languages. Racket's core language includes features such as macros, modules, lexical closures, tail calls, delimited continuations, parameters (fluid variables), software contracts, green threads, and OS threads. The language also comes with primitives, such as event spaces and custodians, which control resource management and enable the language to act like an operating system for loading and managing other programs. Further extensions to the language are created with the powerful macro system, which, together with the module system and custom parsers, can control all aspects of a language. Most language constructs in Racket are implemented as macros in the base language.