hello, world

Curator’s note

One line, no imports, no entry point, no boilerplate of any kind. Of every greeting in this hall, this is the one with the least between the writer and the machine, and it is not an accident of the example — it is the language.

Lua was built to be embedded inside other programs, which meant the whole implementation had to stay small enough to carry around. That constraint shows up everywhere: one data structure for arrays, dictionaries and objects; a handful of types; no classes at all. The reference implementation is around thirty thousand lines of very plain C, and it fits in a corner of a game engine, a router, or a database.

The reward for that restraint is a hall of its own upstairs. Lua is MIT licensed, so unlike most of the languages here its actual source could hang in the Hall of the Commons — the same permission that let it be embedded in tens of thousands of programs also lets a museum put it on a wall.

There is a joke buried in the brevity. This is the shortest program in the hall by a wide margin, and its language is the one most likely to be running inside something you own without your knowing.