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Comment by whatshisface | Hacker News Reader

Amazing that people use YAML if it does that.

Yep. I used to love Yaml back in the day. But two things burned me.

1. Significant whitespace in a data storage file doesn't scale. Yes, eventually someone wants to dump a giant graph of data and the library breaks.

2. Intermixed context on quoteless strings. Intermixing code and data doesn't work reliably. Every where I see it tried I see it break. If you don't want quotes on your strings, then you have to put something on your keywords. A simple @no would have stopped this and other situations.

As an aside, I find it stupid to have multiple names for true, false, and null.

That's an old YAML 1.1 behavior. It was removed in 1.2 (in 2009), though some implementations (looking at you, pyyaml) are still on 1.1.

So YAML is fine with breaking compatibility in minor version bumps?

Semver was not yet common practice when 1.2 was released.

https://yaml.org/spec/1.2.0/ says 2009

Not breaking backwards compatibility in a minor version bump of a data format was absolutely common sense in 2009.

semver.org -- which did an amazing job popularizing this idea -- did not yet have its webpage up in July 2009 (archive.org has it in December)

Guess what was not removed?

    1 : 1,0
    2: 01
    3: 1.0
    4: 1O
    5: 0b1
    6: 0x1
    7: 0i1
    8: hey,
    8.0: oh,
    version: [3.1, "3.1", 3.10, "3.10"]

Gives you:

    {
    "1": "1,0", 
    "2": 1, 
    "3": 1.0, 
    "4": "1O", 
    "5": 1, 
    "6": 1, 
    "7": "0i1", 
    "8": "oh,", 
    "version": [
        3.1, 
        "3.1", 
        3.1, 
        "3.10"
    ]
    }

YAML turns raw literals into strings, except when the string matches a certain format. Then it may turn it into other things, like int or float, and you better know all the rules by heart and be attentive. And not introduce any typo, which of course no human ever does.

That's why yaml is a format for computer and json a format for humans

And that's also why everybody use JSON to configure CI, and use YAML for REST API.

In situations where I'm forced to use YAML, I just use strict JSON to avoid YAML insanity.

You just learn about the edge cases. This applies to everything. There's a number of languages where an empty list/array is truthy and a number where it's falsey. Learn the tool, do some defensive programming (always quote the strings) and you'll be fine.

(This issue was recognised and since yaml 1.2 (2009) the spec says "no" is a string, packages like https://yaml.readthedocs.io/ have migrated a while ago)

This is why I default to TOML for these sorts of lists of things.

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