Trait WellKnown

pub trait WellKnown: 'static + Sized {
    type Deserializer: DeserializeParam<Self>;

    const DE: Self::Deserializer;
}

Parameter type with well-known deserializer.

Conceptually, this means that the type is known to behave well when deserializing data from a Value (ordinarily, using serde::Deserialize).

Implementations

Basic well-known types include:

• bool
• String
• PathBuf
• Signed and unsigned integers, including non-zero variants
• f32, f64

These types use Serde deserializer. Integer types up to and including 64-bit ones only permit integer input. In contrast, u128, i128 and their non-zero counterparts permit either integer or string input because the serde_json object model cannot represent large integers (>u64::MAX or <i64::MIN). Importantly, string representation must be used for such large integers because otherwise they will be converted (with precision loss!) to f64 by internal serde_json logic before they ever enter the smart-config library.

WellKnown is also implemented for more complex types:

Rust type	Deserializer	Expected JSON
Duration	WithUnit	string or object
ByteSize	WithUnit	string or object
Option	Optional†	value, or null, or nothing
Vec, [_; N], HashSet, BTreeSet	Repeated	array
HashMap, BTreeMap	RepeatedEntries	object

† Options handling can be customized via WellKnownOption or CustomKnownOption traits.

Required Associated Constants

const DE: Self::Deserializer

Deserializer instance.

Required Associated Types

type Deserializer: DeserializeParam<Self>

Type of the deserializer used for this type.

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.

Implementations on Foreign Types

impl WellKnown for IpAddr

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for SocketAddr

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for bool

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for f32

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for f64

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for i8

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for i16

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for i32

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for i64

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for i128

Unlike other ints, we allow str inputs for 128-bit ints because serde_json::Value doesn’t support representing 128-bit numbers natively.

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for isize

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for u8

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for u16

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for u32

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for u64

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for u128

Unlike other ints, we allow str inputs for 128-bit ints because serde_json::Value doesn’t support representing 128-bit numbers natively.

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for usize

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for String

const DE: Self::Deserializer

type Deserializer = Serde<{ $crate::_basic_types!($($expecting)+) }>

impl WellKnown for Ipv4Addr

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for Ipv6Addr

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for SocketAddrV4

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for SocketAddrV6

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for Duration

const DE: Self::Deserializer = WithUnit

type Deserializer = WithUnit

impl WellKnown for PathBuf

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroI8

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroI16

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroI32

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroI64

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroI128

Unlike other ints, we allow str inputs for 128-bit ints because serde_json::Value doesn’t support representing 128-bit numbers natively.

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroIsize

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroU8

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroU16

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroU32

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroU64

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroU128

Unlike other ints, we allow str inputs for 128-bit ints because serde_json::Value doesn’t support representing 128-bit numbers natively.

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for NonZeroUsize

const DE: Self::Deserializer

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for Address

Available on crate feature alloy only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for B64

Available on crate feature alloy only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for B128

Available on crate feature alloy only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for B256

Available on crate feature alloy only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for B512

Available on crate feature alloy only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H128

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H160

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H256

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H384

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H512

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for H768

Available on crate feature primitive-types only.

Accepts a hex string with an optional 0x prefix.

const DE: Self::Deserializer = HASH_DE

type Deserializer = Qualified<Serde<{ $crate::_basic_types!($($expecting)+) }>>

impl WellKnown for U8

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U16

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U32

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U64

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U128

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U128

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U160

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U256

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U256

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U512

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl WellKnown for U512

Available on crate feature primitive-types only.

Accepts a hex string with an mandatory 0x prefix. This prefix is required to clearly signal hex encoding so that "34" doesn’t get mistaken for decimal 34.

const DE: Self::Deserializer = HexUintDeserializer

type Deserializer = HexUintDeserializer

impl<K, V> WellKnown for BTreeMap<K, V>

where K: 'static + Eq + Ord + WellKnown, V: 'static + WellKnown,

const DE: Self::Deserializer

type Deserializer = Entries<K, V>

impl<K, V, S> WellKnown for HashMap<K, V, S>

where K: 'static + Eq + Hash + WellKnown, V: 'static + WellKnown, S: 'static + Default + BuildHasher,

const DE: Self::Deserializer

type Deserializer = Entries<K, V>

impl<T> WellKnown for BTreeSet<T>

where T: Eq + Ord + WellKnown,

const DE: Self::Deserializer

type Deserializer = Repeated<<T as WellKnown>::Deserializer>

impl<T, S> WellKnown for HashSet<T, S>

where T: Eq + Hash + WellKnown, S: 'static + Default + BuildHasher,

const DE: Self::Deserializer

type Deserializer = Repeated<<T as WellKnown>::Deserializer>

impl<T: CustomKnownOption> WellKnown for Option<T>

const DE: Self::Deserializer = T::OPT_DE

type Deserializer = <T as CustomKnownOption>::OptDeserializer

impl<T: WellKnown> WellKnown for Vec<T>

const DE: Self::Deserializer

type Deserializer = Repeated<<T as WellKnown>::Deserializer>

impl<T: WellKnown, const N: usize> WellKnown for [T; N]

const DE: Self::Deserializer

type Deserializer = Repeated<<T as WellKnown>::Deserializer>

Implementors

impl WellKnown for ByteSize

const DE: Self::Deserializer = WithUnit

type Deserializer = WithUnit

impl WellKnown for EtherAmount

const DE: Self::Deserializer = WithUnit

type Deserializer = WithUnit

impl WellKnown for SecretString

const DE: Self::Deserializer = FromSecretString

type Deserializer = FromSecretString