I think TOML[1] is a strict upgrade of JSON as a configuration file format. It has exactly the same expressiveness, but much more human-readable.

[1] https://github.com/toml-lang/toml

Arrays are rather ugly in TOML.

Nesting mappings are worse in TOML imo

Jekyll uses YAML, which brings me to the question, what does this do besides JSON that Jekyll doesn't?

I converted this project to Jekyll, using YAML as the config and hosted on Github Pages: https://github.com/DDuarte/JekyllConfigurablePersonalSite

I work at Apiary and we have a format called MSON for writing data structures in Markdown.

https://github.com/apiaryio/mson/

Agree completely.

I have had to configure some relatively large forms in an application using JSON. Its not a particularly easy to read format, and when the nesting is deep its easy to loose a brace, or not notice a trailing comma in a list.

(I don't know if YAML solves all of those problems, but it certainly looks easier to read).

yeah especially when you have nested arrays of JSON objects with a dozen fields with very long text content....simple in practice but not very readable or clean for humans.

Came here to say exactly the same. It's so easy to support both and for anything where a human is expected to edit it by hand then YAML is far less user-hostile.

I can give you my own reasons. I avoid YAML because it's not simple like JSON.

Just look at the YAML spec - http://www.yaml.org/spec/1.2/spec.html

compared to JSON - http://json.org/

and JSON is already everywhere (as a built-in library, a known mime type, etc). I have to go out of my way in order to use YAML.

I guess the other reason is that I never trust projects with names like "Yet Another..." because I feel like it conveys a lack of craftsmanship. Looking at that YAML spec again today, it looks like every feature was thrown into it with little to no discrimination.

The parts you generally use and the length of the spec are entirely different things. This argument is always silly.

There's no need to be rude about it. Your first statement would have sufficed to make your point.

Anyway, I didn't say that I don't use it because of the length of the spec. I said I don't use it because it's orders of magnitude more complex than JSON and I used the spec as an example of that. A bigger spec means a bigger parser and a higher probability that other people will not limit themselves to the parts that "you generally use".

To that, I added that JSON is everywhere already and YAML isn't. My point about the name seems a little silly, but my intuition has served me well over the years.

To be a 'compliant' parser, you generally have to implement the whole spec. The bigger the spec, the more complicated the parser. The less stuff from the spec you use, the less gets tested. What's silly is picking a 'standard' and thinking because you only use a little bit, you're safe.

Just a nitpick. YAML stands for "YAML Ain't Markup Language".

It started out as "Yet another markup language" though - http://yaml.org/spec/history/2001-05-26.html#sec-intro