Nested vec

[sondrelg]

Hi!

Was just wondering if anyone knows a way to handle Vec<Vec<u8>> with deku? I see from the documentation that a Vec<u8> is representable with a count variable (and I've gotten this to work), but I'm struggling to make progress on the nested vec case.

To avoid the x y problem; what I'm really trying to do, is represent Vec<String>. If there's another way to do that, that would also be helpful 👍

Thanks!

[sondrelg]

I guess I could achieve what I'm trying to do by joining the Vec<String> into a single string and representing it as Vec<u8>

[sondrelg]

I found this to be a little simpler:

#[derive(Debug, PartialEq, DekuRead, DekuWrite)]
pub struct DekuString {
    #[deku(bytes = "1")]
    content_len: u8,
    #[deku(count = "content_len")]
    content: Vec<u8>,
}

impl Into<String> for DekuString {
    fn into(self) -> String {
        String::from_utf8_lossy(&self.content).to_string()
    }
}

impl From<String> for DekuString {
    fn from(value: String) -> Self {
        // TODO: Handle u8 conversion
        DekuString { content_len: value.len() as u8, content: Vec::from(value) }
    }
}

and then doing:

#[derive(Debug, PartialEq, DekuRead, DekuWrite)]
pub struct Foo {
    #[deku(bytes = "1")]
    foo_len: u8,
    #[deku(count = "foo_len")]
    foo: Vec<DekuString>,
}

Please let me know if there are better ways 🙇

[wcampbell0x2a]

Only comment I have is that you don't need #[deku(bytes = "1")] for just a u8.