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Comment by wolframhempel | Hacker News Reader

I feel there's a place for YAML and JSON and that they are quite different:

- YAML is for files written or edited by humans - e.g. configuration files for servers with lots of comments and explanations, but generally quite simple key value pairs or basic data structures

- JSON is for files written and consumed by machines. It allows for complex, nested data structures and types, but requires technical knowledge to use.

The problem arises once you start confusing these usecases. I'd argue that once you start writing `'{"a": 1e2}'` in YAML you're quite far outside of its ideal use. I appreciate that feature creep might lead to overly complex configuration files (I remember editing XML config that allowed you to specify for-loops in my earlier days), but really, at a certain point it might be worth taking a step back and reflecting if you're still using the right tool for the right job.

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I agree about the distinction you made from the human perspective and you put it well.

I have always hated YAML, and still to this day, because I cannot write a yaml file, the indentation makes no sense to me and the list syntax is black magic (you actually have several ways to write those, once again the indentation implication is obscure). So while agreeing on the goal to be written/edited by humans to my perspective it fails at it.

Also 1e2 might not be the best example as this is just 100, but as someone who had to pass a lot of neural network training hyper-parameters : passing 1e-3 and so on is definitely a use-case. I am on the negative values Xe-XX (and YAML 1.1 would parsed it OK) but I guess other domains could also use the positive side to pass values (maybe as upper limits like 1e5 or so).

I think the YAML format should have parsed those number formats from the beginning. If this is fixed now, good job, hopefully the default yaml parsers are going to be "fixed". I would still use TOML over YAML any day, waiting for a human-json (some already exist) to be popularized one day.

Offhand, YAML is non-printing-space sensitive, while JSON is not (it's syntax sensitive though). Looking it up, tabs are not supported, which is a HUGE determent for my use cases. (I'm nearly religious on loving tabs and user defined width of single character indent levels.)

A minor change of nesting is easy to accomplish in JSON, while YAML practically requires support from a text editor. JSON _can_ be rendered in a pretty print fashion for easier human editing, and it should still parse correctly irrespectively of how additional non-printing-space is added.

Why would you need text format when only machines are involved?

Because at multiple points humans are involved creating context for the values and later debugging or changing meaning of the values. Fun part it is when you integrate with systems where you even don't talk with the other party - you still need the documentation but as we see how much JSON over HTTP is used it is rather clear why we need text format.

Not sure what context creation means here that requires machines to speak text to each other, and you could debug the converted human-readable format. And JSON is also used much for app user-editable config despite lacking such trivial things as comments, so prevalence may signal some need, but not necessarily the need for the thing used (the awful XML is also widely used)

Yes my only exposure to YAML is for Symfony configuration and it's way better than JSON for this.

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