Discussion on: Stop Using YAML

[Jesse Phillips]

That reminds me of Lua. It isn't turning complete but if it has functions I am curious how serialization works with that.

As a write only config I'd recommend Lua.

[rprije]

I've never used Lua. But I get the impression the goals are a bit different in that Lua aims to be a programming language for embedding into an application and providing a scripting interface for it. As such I think it's probably a bit heavyweight for a simple configuration language. I expect that using it as a configuration language introduces the same problems that config generation introduces in that it can crash or hang which are usually not properties desirable for a configuration language. But, being an embedded language, it does at least mean your application can load it directly instead of config generation needing to be an intermediate step.

This table summarises what I think are some desirable traits in a configuration language, and how well various languages support them:

Language Feature	Binary	INI	JSON	YAML	Lua	Dhall	Config Gen
Human Readable	No	Yes	Yes	Yes	Yes	Yes	Yes
Regular. Simple Parse Rules	No	Yes	Yes	No	Yes	Yes	Yes
Variable Bindings	No	No	No	Sort of (anchors)	Yes	Yes	Yes
Imports	No	No	No	No	Yes	Yes	Yes
Functions	No	No	No	No	Yes	Yes	Yes
Never Crashes (when well-formed)	Yes	Yes	Yes	Yes	No	Yes	No
Never Hangs (when well-formed)	Yes	Yes	Yes	Yes	No	Yes	No
Readily Readable by multiple Languages	No	Yes	Yes	Yes	Yes	Getting There	Yes
Directly readable by the application	Yes	Yes	Yes	Yes	Yes	Yes	No
Validation Support	No	No	Yes (Schema)	Yes (Schema)	No	Yes (strong, static types)	No

[Jesse Phillips]

Agreed. Lua has many problems as pure configuration. But it does have ancestry influence to be a configuration language.

I guess I just think there could have been some work on perfecting what was doing, like a limited subset LSTN (Lua Simple Table Notation).

BTW, I hate Lua as a language.