Deserialize a map into a Vec of keys

[figsoda]

something like

#[serde_as]
#[derive(Deserialize)]
struct Foo {
  #[serde_as(as = "MapKeys<_>")]
  bar: Vec<String>,
}

that will deserialize

{
  "bar": {
    "foo": "bar",
    "baz": 42
  }
}

into

Foo {
  bar: vec!["foo", "baz"],
}

and discard the values

[jonasbb]

Hi, thanks for the suggestion. Do you have a specific data source where that is needed? I wonder which data formats this would be used with and whether they are self describing or not.

[figsoda]

This would be helpful for parsing pyproject poetry dependencies and discarding the version requirements, this is the solution I am using right now: https://github.com/nix-community/nix-init/blob/6c9f7838f58bb361ed692919eca26bb18ce87f47/src/python.rs#L27-L60, and I had to write extra boilerplate code for PoetryDependency just to be discarded

this is very similar to cargo's dependencies section, so you can just imagine that if that's easier for you, basically something like

anyhow = "1.0.68"
askalono = "0.4.6"
bstr = "1.1.0"
expand = "0.2.1"

would yield something like ["anyhow", "askalono", "bstr", "expand"] (but BTreeSet<String> in my case)