How extensible are they? As far I can see they are at a "structure level" (I'm not sure if there is proper term for it; by "structure level" I mean extending some language with structures like in C in place of a type (joining few types together), for example (pseudocode): `qux: struct {foo: string, baz: integer}; qux new-variable = struct {foo: "***", baz: 42}`) or are they extensible at deeper level (parsing types, e.g. `new-type: <"-">; new-type new-variable = 2-3)?

I don't want to waste time on your trolling.

Well, pointing XML/JSON was off topic as well.

I don't mean that I won't use XML/JSON. I think they are not good enough so I still want to create my data notation. It's just me saying that this is off topic (I used stackexchange sites before) and I just don't want to discuss it any farther (as it doesn't bring anything to my first question).

They are not good enough so I won't use it.

While binary format described by you is interesting it's not what I asked about. I'll try creating one in the future nevertheless.

XML is very verbose and JSON doesn't have extendable types.

> Why optimize for concise? To save YOU time typing? I don't think typing is a problem when you have IDEs with autocompletion. The problem is reading. Sure, your IDE will colour this and that but you still have, for example, whole line just saying " is the name of the function".

I want to create data notation (like JSON is used). 1) Is it good enough to use languages built-in features (types, notation etc), extend it (e.g. with another types), and output some JSON? 2) Or should I build it from scratch and parse all built-in features and add my additions then output it into JSON? By using 1) I don't have to implement core things. If there are fixes - then it's good. If there are changes that I don't like I can deal with them from case to case... I guess. Howerer I'm tied to a programming language - so users had to use the programming language (instead library). By using 2) I have to build everything but I'm not tied to one particular language. Maybe I can mix it ( 1) for the language, 2) for other languages). What are your toughts on this topic. ps. I was thinking about using the Red ( red-lang.org/ ). It's in alpha but I don't think it will change a lot.

Kotlin: maybe not best "human-understandable" but it takes Java and make it more concise. You don't have to write many things the Kotlin that you write in the Java. Red: it's still in the alpha version but you should keep an eye on it. You can write in different styles but you can write small & concise code. It has some "weird features". Ruby: It might be not fastest language but it's very readable. No "parenthesis hell" (same as in the Red) as in other languages.