> is that for a long time it was the only viable configuration format

Actually, this is not the case. We had INI format for simple stuff and XML (protected with entire schema) for complex things many years ago, which worked. Yet, we wanted something readable (like INI), but able to express complex types (XML).

I don't think Toml is a viable replacement - for me, it has an INI-level of simplicity with even worst hacks to have nested structures. But, give it time and you'll have another YAML.

But yes, YAML is confusing for edge cases (true/false, quoting), but I'm going to find a powerful replacement that is not XML. Maybe EDN can jump in, but for anything more complex, I'd rather have a Lisp interpreter and structures around than any of mentioned and upcoming formats.

Thinking that JSON is a suitable replacement, imagine writing Ansible or k8s stuff in it; that would be fun ;)

INI has no spec, and there are many variations all slightly incompatible with each other, kinda like Markdown. YAML is really the only sane configuration language that lets you denote nested structures while keeping them look nested.

Basically, all of the problem identified in the article can be dealt with 1 rule - always quote your strings. I agree with the author we should have reduced, safe and minimalist subset of yaml, which is basically YAML 1.2, released in 2009.

P.S. Please just stop using PyYAML.

I second that. And if people need to deal with YAML in Python, they should be using ruamel.yaml, which is a far superior library on just about every level: https://pypi.org/project/ruamel.yaml/