Why does Lua lack the += operator, etc.?
One of Lua’s design goals is simplicity. Most languages are large, meaning that they have many sophisticated features built-in. Examples are C, C++, Python, Lisp, ML. A very few languages are small. Examples are Forth and Lua. Lua aims to provide a small range of atomic features which are truly essential, and from which many other sophisticated features can be constructed if desired. Examples of sophisticated features which can be added to Lua from within the language include modules, object orientation, and now exceptions and threads which can be implemented via coroutines in Lua 5. The absent += operator is one more example. I thought the reason was more practical. Many argue for adding these operators because of the efficiency gains they enable. But in Lua things would get confusing because of the extension system. It’s in the lua-l archives somewhere… –JohnBelmonte I think it’s more basic than that – you must draw a line in the sand for the amount of operators a small language s
