Wren is a small, fast, class-based concurrent scripting language #

Think Smalltalk in a Lua-sized package with a dash of Erlang and wrapped up in a familiar, modern syntax.

System.print("Hello, world!") class Wren { flyTo(city) { System.print("Flying to %(city)") } } var adjectives = Fiber.new { ["small", "clean", "fast"].each {|word| Fiber.yield(word) } } while (!adjectives.isDone) System.print(adjectives.call())

Wren is small. The VM implementation is under 4,000 semicolons. You can skim the whole thing in an afternoon. It’s small, but not dense. It is readable and lovingly-commented.

Wren is fast. A fast single-pass compiler to tight bytecode, and a compact object representation help Wren compete with other dynamic languages.

Wren is class-based. There are lots of scripting languages out there, but many have unusual or non-existent object models. Wren places classes front and center.

Wren is concurrent. Lightweight fibers are core to the execution model and let you organize your program into a flock of communicating coroutines.

Wren is a scripting language. Wren is intended for embedding in applications. It has no dependencies, a small standard library, and an easy-to-use C API. It compiles cleanly as C99, C++98 or anything later.

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