As long as you don't skip a numeric key, you can rely on the length operator for "array-like" tables. There's no built-in way to check the length of a "dictiona

As long as you don't skip a numeric key, you can rely on the length operator for "array-like" tables. There's no built-in way to check the length of a "dictionary-like" table, but you can overload the length operator in Lua >= 5.2 or LuaJIT. The base language is very simple, but you usually have the building blocks necessary to add the behavior you're missing.