edn VS lua-patterns

> was utterly surprised how no one ever apparently has thought to create a configuration/templating system that's basically a fancy library on top of Scheme.

There's Clojure's extensible data notation: https://github.com/edn-format/edn

A thin language layer around edn/datalog, the query language

EDN (Extensible Data Notation) is a subset of Clojure: https://github.com/edn-format/edn

It is:

- Streamable

- Extensible

- Whitespace-insensitive, but there are formatting conventions for readability

To begin with, EDN is somewhat like the JSON of Clojure. And regarding the code is data/data is code nature of Clojure, it is Clojure. It doesn't have some of the vagaries of JSON, and it is also extensible.

Alien is not a reason something is bad, just that's it's unusual. JSON was a bit alien when it first arrived as well, as everyone was used to XML at the time.

`{num 5, val 4}` looks fine to me, but we can do even better! We already know objects/maps are always in pairs, so we don't really need that comma either. Just do `{num 5 val 4}` and we save yet another unnecessary characters.

Of course, I didn't come up with this format myself, what I actually want JSON to be is EDN (https://github.com/edn-format/edn) which is a standalone format but also directly used in Clojure, so it already exists inside a programming language and works very well. There keys are strings though, so you example would end up being `{"num" 5 "val" 5 "person" var}`, where commas are optional.

I just checked out the spec, and it gets pretty ugly in the Table section. A lot of the json examples are both shorter and IMO more precise. Stuff that’s not allowed with [table] is allowed with [[table]], and it’s confusing to understand what level of depth I’m at.

I’ll take edn over any of “em. https://github.com/edn-format/edn

As XT is written in Clojure and it natively supports Clojure’s data types, we were not satisfied with available JSON types and decided to give EDN a try - that way we would have way more supported types:

Compare the nightmare that is pickling with how simple it is to serialize pure data with edn in clojure. What ends up happening is people passing around JSONs or whatever and writing parsing/encoding code at each end, which makes things unnecessarily more complex, and dangerous, and error prone, and boring, etc...

If you want automatic built-in string validation, one option that seems particularly interesting is to use a variant of Lua patterns, which are weaker and easier to understand than regular expressions, but still provide a significant degree of "sanity" for something like an email. The original version works on bytes and not runes, but you could simply write a parser that works on runes instead, and the pattern-matching code is just 400 old and battle-tested lines of C89.

Lua patterns have also shown up in other places, such as BSD's httpd, and an implementation for Rust:

https://www.gsp.com/cgi-bin/man.cgi?section=7&topic=PATTERNS

https://github.com/stevedonovan/lua-patterns

http://lua-users.org/wiki/PatternsTutorial