Module encdec::decode

Decode traits and helper macros

Example

#[derive(Debug, PartialEq)]
struct SomethingOwned {
    a: u8,
    b: u16,
    c: [u8; 3],
}

/// [`DecodeOwned`] implementation for self-contained types.
impl DecodeOwned for SomethingOwned {
    type Output = Self;
    type Error = Error;

   /// Decode object from provided buffer, returning object and decoded
   /// length on success
   fn decode_owned(buff: &[u8]) -> Result<(Self::Output, usize), Self::Error> {
        let mut index = 0;

        let a = buff[0];
        index += 1;

        let b = buff[1] as u16 | (buff[2] as u16) << 8;
        index += 2;

        let mut c = [0u8; 3];
        c.copy_from_slice(&buff[3..][..3]);
        index += 3;

        Ok((Self{a, b, c}, index))
   }
}

#[derive(Debug, PartialEq)]
struct SomethingBorrowed<'a> {
    a: u8,
    l: u16,
    c: &'a [u8],
}

/// Base [`Decode`] implementation, lifetime support for views
/// into borrowed buffers. If you don't need this, see [`DecodeOwned`].
impl <'a>Decode<'a> for SomethingBorrowed<'a> {
    type Output = SomethingBorrowed<'a>;
    type Error = Error;

   /// Decode object from provided buffer, returning object and decoded
   /// length on success
   fn decode(buff: &'a [u8]) -> Result<(Self::Output, usize), Self::Error> {
        let mut index = 0;

        let a = buff[0];
        index += 1;

        // using `l` as the length of `c`
        let l = buff[1] as u16 | (buff[2] as u16) << 8;
        index += 2;

        let c = &buff[index..][..l as usize];

        Ok((Self{a, l, c}, index))
   }
}

Structs

DecodeIter

Helper type for parsing lists of decodable objects (with internal length delimiters)

Traits

Decode

Decode trait implemented for binary decodable objects

DecodeExt

Extensions to Decode trait for decodable objects

DecodeOwned

Decode trait implemented for owned types

DecodePrefixed

Decode helper trait for fields with length prefixes

DecodedTagged

Decode helper trait for for fields with external length tags (length must be specified via #[encdec(length=...)] macro)

Derive Macros

Decode

#[derive(Decode)] support.

DecodeOwned

#[derive(DecodeOwned)] support.