It's in the standard library for Python, Rust, Julia, and maybe some other languages. It's also widely used in those ecosystems (pyproject.toml, cargo.toml). I think it's fair to say it took off, even though YAML is also popular.
The tomllib library in Python 3.11+ can only read TOML files, not write them.
I don't believe its in the standard library for Rust, even if it is very popular in the Rust ecosystem.
Right; I'm not super-familiar with Rust and how exactly they organise things, but it's in more or less every Rust project due to Cargo.toml.
Rust uses it, and Rust seems pretty popular.
I know Alire, the Ada crate manager uses it too.
I use it for some personal projects. It's really nice!
Which is hilarious when you consider that the spec is that complex.
Toml is both great and terrible. I'm not a fan of how it handles some deeper arrays