Trait Decode

Source

pub trait Decode<'b, C>: Sized {
    // Required method
    fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Self, Error>;

    // Provided method
    fn nil() -> Option<Self> { ... }
}

Expand description

A type that can be decoded from CBOR.

Required Methods§

Source

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Self, Error>

Decode a value using the given Decoder.

In addition to the decoder a user provided decoding context is given as another parameter. Most implementations of this trait do not need a decoding context and should be completely generic in the context type. In cases where a context is needed and the Decode impl type is meant to be combined with other types that require a different context type, it is preferrable to constrain the context type variable C with a trait bound instead of fixing the type.

Provided Methods§

Source

fn nil() -> Option<Self>

If possible, return a nil value of Self.

This method is primarily used by minicbor-derive and allows creating a special value denoting the absence of a “real” value if no CBOR value is present. The canonical example of a type where this is sensible is the Option type, whose Decode::nil method would return Some(None).

With the exception of Option<_> all types T are considered mandatory by default, i.e. T::nil() returns None. Missing values of T therefore cause decoding errors in derived Decode implementations.

NB: A type implementing Decode with an overriden Decode::nil method should also override Encode::is_nil if it implements Encode at all.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Trait Decode Copy item path

Required Methods§

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Self, Error>

Provided Methods§

fn nil() -> Option<Self>

Dyn Compatibility§

Implementations on Foreign Types§

impl<'a, 'b, C> Decode<'b, C> for &'a strwhere 'b: 'a,

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<&'a str, Error>

impl<'a, 'b, C> Decode<'b, C> for &'a CStrwhere 'b: 'a,

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<&'a CStr, Error>

impl<'a, 'b, C> Decode<'b, C> for &'a Pathwhere 'b: 'a,

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<&'a Path, Error>

impl<'b, C> Decode<'b, C> for IpAddr

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<IpAddr, Error>

impl<'b, C> Decode<'b, C> for SocketAddr

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<SocketAddr, Error>

impl<'b, C> Decode<'b, C> for AddrDistr

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<AddrDistr, Error>

impl<'b, C> Decode<'b, C> for SpendingData

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<SpendingData, Error>

impl<'b, C> Decode<'b, C> for AnyUInt

fn decode(d: &mut Decoder<'b>, _ctx: &mut C) -> Result<AnyUInt, Error>

impl<'b, C> Decode<'b, C> for AuxiliaryData

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<AuxiliaryData, Error>

impl<'b, C> Decode<'b, C> for Certificate

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Certificate, Error>

impl<'b, C> Decode<'b, C> for InstantaneousRewardSource

fn decode( d: &mut Decoder<'b>, _ctx: &mut C, ) -> Result<InstantaneousRewardSource, Error>

impl<'b, C> Decode<'b, C> for InstantaneousRewardTarget

fn decode( d: &mut Decoder<'b>, ctx: &mut C, ) -> Result<InstantaneousRewardTarget, Error>

impl<'b, C> Decode<'b, C> for Value

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Value, Error>

impl<'b, C> Decode<'b, C> for BlockSig

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<BlockSig, Error>

impl<'b, C> Decode<'b, C> for Ssc

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Ssc, Error>

impl<'b, C> Decode<'b, C> for SscProof

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<SscProof, Error>

impl<'b, C> Decode<'b, C> for Twit

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Twit, Error>

impl<'b, C> Decode<'b, C> for TxFeePol

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<TxFeePol, Error>

impl<'b, C> Decode<'b, C> for TxIn

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<TxIn, Error>

impl<'b, C> Decode<'b, C> for Metadatum

fn decode(d: &mut Decoder<'b>, ctx: &mut C) -> Result<Metadatum, Error>

impl<'b, C> Decode<'b, C> for bool

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<bool, Error>

impl<'b, C> Decode<'b, C> for char

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<char, Error>

impl<'b, C> Decode<'b, C> for f32

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<f32, Error>

impl<'b, C> Decode<'b, C> for f64

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<f64, Error>

impl<'b, C> Decode<'b, C> for i8

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<i8, Error>

impl<'b, C> Decode<'b, C> for i16

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<i16, Error>

impl<'b, C> Decode<'b, C> for i32

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<i32, Error>

impl<'b, C> Decode<'b, C> for i64

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<i64, Error>

impl<'b, C> Decode<'b, C> for isize

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<isize, Error>

impl<'b, C> Decode<'b, C> for u8

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<u8, Error>

impl<'b, C> Decode<'b, C> for u16

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<u16, Error>

impl<'b, C> Decode<'b, C> for u32

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<u32, Error>

impl<'b, C> Decode<'b, C> for u64

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<u64, Error>

impl<'b, C> Decode<'b, C> for ()

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<(), Error>

impl<'b, C> Decode<'b, C> for usize

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<usize, Error>

impl<'b, C> Decode<'b, C> for Box<str>

fn decode(d: &mut Decoder<'b>, _: &mut C) -> Result<Box<str>, Error>

impl<'b, C> Decode<'b, C> for Box<Path>

Trait Decode

impl<'a, 'b, C> Decode<'b, C> for &'a str
where 'b: 'a,

impl<'a, 'b, C> Decode<'b, C> for &'a CStr
where 'b: 'a,

impl<'a, 'b, C> Decode<'b, C> for &'a Path
where 'b: 'a,