Trait serde::Serializer
source · [−]pub trait Serializer: Sized {
type Ok;
type Error: Error;
type SerializeSeq: SerializeSeq<Ok = Self::Ok, Error = Self::Error>;
type SerializeTuple: SerializeTuple<Ok = Self::Ok, Error = Self::Error>;
type SerializeTupleStruct: SerializeTupleStruct<Ok = Self::Ok, Error = Self::Error>;
type SerializeTupleVariant: SerializeTupleVariant<Ok = Self::Ok, Error = Self::Error>;
type SerializeMap: SerializeMap<Ok = Self::Ok, Error = Self::Error>;
type SerializeStruct: SerializeStruct<Ok = Self::Ok, Error = Self::Error>;
type SerializeStructVariant: SerializeStructVariant<Ok = Self::Ok, Error = Self::Error>;
Show 34 methods
fn serialize_bool(self, v: bool) -> Result<Self::Ok, Self::Error>;
fn serialize_i8(self, v: i8) -> Result<Self::Ok, Self::Error>;
fn serialize_i16(self, v: i16) -> Result<Self::Ok, Self::Error>;
fn serialize_i32(self, v: i32) -> Result<Self::Ok, Self::Error>;
fn serialize_i64(self, v: i64) -> Result<Self::Ok, Self::Error>;
fn serialize_u8(self, v: u8) -> Result<Self::Ok, Self::Error>;
fn serialize_u16(self, v: u16) -> Result<Self::Ok, Self::Error>;
fn serialize_u32(self, v: u32) -> Result<Self::Ok, Self::Error>;
fn serialize_u64(self, v: u64) -> Result<Self::Ok, Self::Error>;
fn serialize_f32(self, v: f32) -> Result<Self::Ok, Self::Error>;
fn serialize_f64(self, v: f64) -> Result<Self::Ok, Self::Error>;
fn serialize_char(self, v: char) -> Result<Self::Ok, Self::Error>;
fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error>;
fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error>;
fn serialize_none(self) -> Result<Self::Ok, Self::Error>;
fn serialize_some<T: ?Sized>(
self,
value: &T
) -> Result<Self::Ok, Self::Error>
where
T: Serialize;
fn serialize_unit(self) -> Result<Self::Ok, Self::Error>;
fn serialize_unit_struct(
self,
name: &'static str
) -> Result<Self::Ok, Self::Error>;
fn serialize_unit_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str
) -> Result<Self::Ok, Self::Error>;
fn serialize_newtype_struct<T: ?Sized>(
self,
name: &'static str,
value: &T
) -> Result<Self::Ok, Self::Error>
where
T: Serialize;
fn serialize_newtype_variant<T: ?Sized>(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
value: &T
) -> Result<Self::Ok, Self::Error>
where
T: Serialize;
fn serialize_seq(
self,
len: Option<usize>
) -> Result<Self::SerializeSeq, Self::Error>;
fn serialize_tuple(
self,
len: usize
) -> Result<Self::SerializeTuple, Self::Error>;
fn serialize_tuple_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeTupleStruct, Self::Error>;
fn serialize_tuple_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeTupleVariant, Self::Error>;
fn serialize_map(
self,
len: Option<usize>
) -> Result<Self::SerializeMap, Self::Error>;
fn serialize_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeStruct, Self::Error>;
fn serialize_struct_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeStructVariant, Self::Error>;
fn serialize_i128(self, v: i128) -> Result<Self::Ok, Self::Error> { ... }
fn serialize_u128(self, v: u128) -> Result<Self::Ok, Self::Error> { ... }
fn collect_seq<I>(self, iter: I) -> Result<Self::Ok, Self::Error>
where
I: IntoIterator,
<I as IntoIterator>::Item: Serialize,
{ ... }
fn collect_map<K, V, I>(self, iter: I) -> Result<Self::Ok, Self::Error>
where
K: Serialize,
V: Serialize,
I: IntoIterator<Item = (K, V)>,
{ ... }
fn collect_str<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error>
where
T: Display,
{ ... }
fn is_human_readable(&self) -> bool { ... }
}
Expand description
A data format that can serialize any data structure supported by Serde.
The role of this trait is to define the serialization half of the Serde
data model, which is a way to categorize every Rust data structure into one
of 29 possible types. Each method of the Serializer
trait corresponds to
one of the types of the data model.
Implementations of Serialize
map themselves into this data model by
invoking exactly one of the Serializer
methods.
The types that make up the Serde data model are:
- 14 primitive types
- bool
- i8, i16, i32, i64, i128
- u8, u16, u32, u64, u128
- f32, f64
- char
- string
- UTF-8 bytes with a length and no null terminator.
- When serializing, all strings are handled equally. When deserializing, there are three flavors of strings: transient, owned, and borrowed.
- byte array - [u8]
- Similar to strings, during deserialization byte arrays can be transient, owned, or borrowed.
- option
- Either none or some value.
- unit
- The type of
()
in Rust. It represents an anonymous value containing no data.
- The type of
- unit_struct
- For example
struct Unit
orPhantomData<T>
. It represents a named value containing no data.
- For example
- unit_variant
- For example the
E::A
andE::B
inenum E { A, B }
.
- For example the
- newtype_struct
- For example
struct Millimeters(u8)
.
- For example
- newtype_variant
- For example the
E::N
inenum E { N(u8) }
.
- For example the
- seq
- A variably sized heterogeneous sequence of values, for example
Vec<T>
orHashSet<T>
. When serializing, the length may or may not be known before iterating through all the data. When deserializing, the length is determined by looking at the serialized data.
- A variably sized heterogeneous sequence of values, for example
- tuple
- A statically sized heterogeneous sequence of values for which the
length will be known at deserialization time without looking at the
serialized data, for example
(u8,)
or(String, u64, Vec<T>)
or[u64; 10]
.
- A statically sized heterogeneous sequence of values for which the
length will be known at deserialization time without looking at the
serialized data, for example
- tuple_struct
- A named tuple, for example
struct Rgb(u8, u8, u8)
.
- A named tuple, for example
- tuple_variant
- For example the
E::T
inenum E { T(u8, u8) }
.
- For example the
- map
- A heterogeneous key-value pairing, for example
BTreeMap<K, V>
.
- A heterogeneous key-value pairing, for example
- struct
- A heterogeneous key-value pairing in which the keys are strings and
will be known at deserialization time without looking at the
serialized data, for example
struct S { r: u8, g: u8, b: u8 }
.
- A heterogeneous key-value pairing in which the keys are strings and
will be known at deserialization time without looking at the
serialized data, for example
- struct_variant
- For example the
E::S
inenum E { S { r: u8, g: u8, b: u8 } }
.
- For example the
Many Serde serializers produce text or binary data as output, for example
JSON or Postcard. This is not a requirement of the Serializer
trait, and
there are serializers that do not produce text or binary output. One example
is the serde_json::value::Serializer
(distinct from the main serde_json
serializer) that produces a serde_json::Value
data structure in memory as
output.
Example implementation
The example data format presented on the website contains example code for
a basic JSON Serializer
.
Required Associated Types
The output type produced by this Serializer
during successful
serialization. Most serializers that produce text or binary output
should set Ok = ()
and serialize into an io::Write
or buffer
contained within the Serializer
instance. Serializers that build
in-memory data structures may be simplified by using Ok
to propagate
the data structure around.
type SerializeSeq: SerializeSeq<Ok = Self::Ok, Error = Self::Error>
type SerializeSeq: SerializeSeq<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_seq
for serializing the content of the
sequence.
type SerializeTuple: SerializeTuple<Ok = Self::Ok, Error = Self::Error>
type SerializeTuple: SerializeTuple<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_tuple
for serializing the content of
the tuple.
type SerializeTupleStruct: SerializeTupleStruct<Ok = Self::Ok, Error = Self::Error>
type SerializeTupleStruct: SerializeTupleStruct<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_tuple_struct
for serializing the
content of the tuple struct.
type SerializeTupleVariant: SerializeTupleVariant<Ok = Self::Ok, Error = Self::Error>
type SerializeTupleVariant: SerializeTupleVariant<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_tuple_variant
for serializing the
content of the tuple variant.
type SerializeMap: SerializeMap<Ok = Self::Ok, Error = Self::Error>
type SerializeMap: SerializeMap<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_map
for serializing the content of the
map.
type SerializeStruct: SerializeStruct<Ok = Self::Ok, Error = Self::Error>
type SerializeStruct: SerializeStruct<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_struct
for serializing the content of
the struct.
type SerializeStructVariant: SerializeStructVariant<Ok = Self::Ok, Error = Self::Error>
type SerializeStructVariant: SerializeStructVariant<Ok = Self::Ok, Error = Self::Error>
Type returned from serialize_struct_variant
for serializing the
content of the struct variant.
Required Methods
Serialize a bool
value.
impl Serialize for bool {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_bool(*self)
}
}
Serialize an i8
value.
If the format does not differentiate between i8
and i64
, a
reasonable implementation would be to cast the value to i64
and
forward to serialize_i64
.
impl Serialize for i8 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_i8(*self)
}
}
Serialize an i16
value.
If the format does not differentiate between i16
and i64
, a
reasonable implementation would be to cast the value to i64
and
forward to serialize_i64
.
impl Serialize for i16 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_i16(*self)
}
}
Serialize an i32
value.
If the format does not differentiate between i32
and i64
, a
reasonable implementation would be to cast the value to i64
and
forward to serialize_i64
.
impl Serialize for i32 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_i32(*self)
}
}
Serialize an i64
value.
impl Serialize for i64 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_i64(*self)
}
}
Serialize a u8
value.
If the format does not differentiate between u8
and u64
, a
reasonable implementation would be to cast the value to u64
and
forward to serialize_u64
.
impl Serialize for u8 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_u8(*self)
}
}
Serialize a u16
value.
If the format does not differentiate between u16
and u64
, a
reasonable implementation would be to cast the value to u64
and
forward to serialize_u64
.
impl Serialize for u16 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_u16(*self)
}
}
Serialize a u32
value.
If the format does not differentiate between u32
and u64
, a
reasonable implementation would be to cast the value to u64
and
forward to serialize_u64
.
impl Serialize for u32 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_u32(*self)
}
}
Serialize a u64
value.
impl Serialize for u64 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_u64(*self)
}
}
Serialize an f32
value.
If the format does not differentiate between f32
and f64
, a
reasonable implementation would be to cast the value to f64
and
forward to serialize_f64
.
impl Serialize for f32 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_f32(*self)
}
}
Serialize an f64
value.
impl Serialize for f64 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_f64(*self)
}
}
Serialize a character.
If the format does not support characters, it is reasonable to serialize
it as a single element str
or a u32
.
impl Serialize for char {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_char(*self)
}
}
Serialize a &str
.
impl Serialize for str {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_str(self)
}
}
Serialize a chunk of raw byte data.
Enables serializers to serialize byte slices more compactly or more
efficiently than other types of slices. If no efficient implementation
is available, a reasonable implementation would be to forward to
serialize_seq
. If forwarded, the implementation looks usually just
like this:
fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error> {
let mut seq = self.serialize_seq(Some(v.len()))?;
for b in v {
seq.serialize_element(b)?;
}
seq.end()
}
fn serialize_none(self) -> Result<Self::Ok, Self::Error>
fn serialize_none(self) -> Result<Self::Ok, Self::Error>
Serialize a None
value.
impl<T> Serialize for Option<T>
where
T: Serialize,
{
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
Some(ref value) => serializer.serialize_some(value),
None => serializer.serialize_none(),
}
}
}
Serialize a Some(T)
value.
impl<T> Serialize for Option<T>
where
T: Serialize,
{
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
Some(ref value) => serializer.serialize_some(value),
None => serializer.serialize_none(),
}
}
}
fn serialize_unit(self) -> Result<Self::Ok, Self::Error>
fn serialize_unit(self) -> Result<Self::Ok, Self::Error>
Serialize a ()
value.
impl Serialize for () {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_unit()
}
}
Serialize a unit struct like struct Unit
or PhantomData<T>
.
A reasonable implementation would be to forward to serialize_unit
.
use serde::{Serialize, Serializer};
struct Nothing;
impl Serialize for Nothing {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_unit_struct("Nothing")
}
}
Serialize a unit variant like E::A
in enum E { A, B }
.
The name
is the name of the enum, the variant_index
is the index of
this variant within the enum, and the variant
is the name of the
variant.
use serde::{Serialize, Serializer};
enum E {
A,
B,
}
impl Serialize for E {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
E::A => serializer.serialize_unit_variant("E", 0, "A"),
E::B => serializer.serialize_unit_variant("E", 1, "B"),
}
}
}
Serialize a newtype struct like struct Millimeters(u8)
.
Serializers are encouraged to treat newtype structs as insignificant
wrappers around the data they contain. A reasonable implementation would
be to forward to value.serialize(self)
.
use serde::{Serialize, Serializer};
struct Millimeters(u8);
impl Serialize for Millimeters {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_newtype_struct("Millimeters", &self.0)
}
}
Serialize a newtype variant like E::N
in enum E { N(u8) }
.
The name
is the name of the enum, the variant_index
is the index of
this variant within the enum, and the variant
is the name of the
variant. The value
is the data contained within this newtype variant.
use serde::{Serialize, Serializer};
enum E {
M(String),
N(u8),
}
impl Serialize for E {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
E::M(ref s) => serializer.serialize_newtype_variant("E", 0, "M", s),
E::N(n) => serializer.serialize_newtype_variant("E", 1, "N", &n),
}
}
}
fn serialize_seq(
self,
len: Option<usize>
) -> Result<Self::SerializeSeq, Self::Error>
fn serialize_seq(
self,
len: Option<usize>
) -> Result<Self::SerializeSeq, Self::Error>
Begin to serialize a variably sized sequence. This call must be
followed by zero or more calls to serialize_element
, then a call to
end
.
The argument is the number of elements in the sequence, which may or may not be computable before the sequence is iterated. Some serializers only support sequences whose length is known up front.
use serde::ser::{Serialize, Serializer, SerializeSeq};
impl<T> Serialize for Vec<T>
where
T: Serialize,
{
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut seq = serializer.serialize_seq(Some(self.len()))?;
for element in self {
seq.serialize_element(element)?;
}
seq.end()
}
}
fn serialize_tuple(
self,
len: usize
) -> Result<Self::SerializeTuple, Self::Error>
fn serialize_tuple(
self,
len: usize
) -> Result<Self::SerializeTuple, Self::Error>
Begin to serialize a statically sized sequence whose length will be
known at deserialization time without looking at the serialized data.
This call must be followed by zero or more calls to serialize_element
,
then a call to end
.
use serde::ser::{Serialize, Serializer, SerializeTuple};
impl<A, B, C> Serialize for (A, B, C)
where
A: Serialize,
B: Serialize,
C: Serialize,
{
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut tup = serializer.serialize_tuple(3)?;
tup.serialize_element(&self.0)?;
tup.serialize_element(&self.1)?;
tup.serialize_element(&self.2)?;
tup.end()
}
}
use serde::ser::{Serialize, SerializeTuple, Serializer};
const VRAM_SIZE: usize = 386;
struct Vram([u16; VRAM_SIZE]);
impl Serialize for Vram {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut seq = serializer.serialize_tuple(VRAM_SIZE)?;
for element in &self.0[..] {
seq.serialize_element(element)?;
}
seq.end()
}
}
fn serialize_tuple_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeTupleStruct, Self::Error>
fn serialize_tuple_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeTupleStruct, Self::Error>
Begin to serialize a tuple struct like struct Rgb(u8, u8, u8)
. This
call must be followed by zero or more calls to serialize_field
, then a
call to end
.
The name
is the name of the tuple struct and the len
is the number
of data fields that will be serialized.
use serde::ser::{Serialize, SerializeTupleStruct, Serializer};
struct Rgb(u8, u8, u8);
impl Serialize for Rgb {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut ts = serializer.serialize_tuple_struct("Rgb", 3)?;
ts.serialize_field(&self.0)?;
ts.serialize_field(&self.1)?;
ts.serialize_field(&self.2)?;
ts.end()
}
}
fn serialize_tuple_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeTupleVariant, Self::Error>
fn serialize_tuple_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeTupleVariant, Self::Error>
Begin to serialize a tuple variant like E::T
in enum E { T(u8, u8) }
. This call must be followed by zero or more calls to
serialize_field
, then a call to end
.
The name
is the name of the enum, the variant_index
is the index of
this variant within the enum, the variant
is the name of the variant,
and the len
is the number of data fields that will be serialized.
use serde::ser::{Serialize, SerializeTupleVariant, Serializer};
enum E {
T(u8, u8),
U(String, u32, u32),
}
impl Serialize for E {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
E::T(ref a, ref b) => {
let mut tv = serializer.serialize_tuple_variant("E", 0, "T", 2)?;
tv.serialize_field(a)?;
tv.serialize_field(b)?;
tv.end()
}
E::U(ref a, ref b, ref c) => {
let mut tv = serializer.serialize_tuple_variant("E", 1, "U", 3)?;
tv.serialize_field(a)?;
tv.serialize_field(b)?;
tv.serialize_field(c)?;
tv.end()
}
}
}
}
fn serialize_map(
self,
len: Option<usize>
) -> Result<Self::SerializeMap, Self::Error>
fn serialize_map(
self,
len: Option<usize>
) -> Result<Self::SerializeMap, Self::Error>
Begin to serialize a map. This call must be followed by zero or more
calls to serialize_key
and serialize_value
, then a call to end
.
The argument is the number of elements in the map, which may or may not be computable before the map is iterated. Some serializers only support maps whose length is known up front.
use serde::ser::{Serialize, Serializer, SerializeMap};
impl<K, V> Serialize for HashMap<K, V>
where
K: Serialize,
V: Serialize,
{
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut map = serializer.serialize_map(Some(self.len()))?;
for (k, v) in self {
map.serialize_entry(k, v)?;
}
map.end()
}
}
fn serialize_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeStruct, Self::Error>
fn serialize_struct(
self,
name: &'static str,
len: usize
) -> Result<Self::SerializeStruct, Self::Error>
Begin to serialize a struct like struct Rgb { r: u8, g: u8, b: u8 }
.
This call must be followed by zero or more calls to serialize_field
,
then a call to end
.
The name
is the name of the struct and the len
is the number of
data fields that will be serialized.
use serde::ser::{Serialize, SerializeStruct, Serializer};
struct Rgb {
r: u8,
g: u8,
b: u8,
}
impl Serialize for Rgb {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut rgb = serializer.serialize_struct("Rgb", 3)?;
rgb.serialize_field("r", &self.r)?;
rgb.serialize_field("g", &self.g)?;
rgb.serialize_field("b", &self.b)?;
rgb.end()
}
}
fn serialize_struct_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeStructVariant, Self::Error>
fn serialize_struct_variant(
self,
name: &'static str,
variant_index: u32,
variant: &'static str,
len: usize
) -> Result<Self::SerializeStructVariant, Self::Error>
Begin to serialize a struct variant like E::S
in enum E { S { r: u8, g: u8, b: u8 } }
. This call must be followed by zero or more calls to
serialize_field
, then a call to end
.
The name
is the name of the enum, the variant_index
is the index of
this variant within the enum, the variant
is the name of the variant,
and the len
is the number of data fields that will be serialized.
use serde::ser::{Serialize, SerializeStructVariant, Serializer};
enum E {
S { r: u8, g: u8, b: u8 },
}
impl Serialize for E {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match *self {
E::S {
ref r,
ref g,
ref b,
} => {
let mut sv = serializer.serialize_struct_variant("E", 0, "S", 3)?;
sv.serialize_field("r", r)?;
sv.serialize_field("g", g)?;
sv.serialize_field("b", b)?;
sv.end()
}
}
}
}
Provided Methods
Serialize an i128
value.
impl Serialize for i128 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_i128(*self)
}
}
This method is available only on Rust compiler versions >=1.26. The default behavior unconditionally returns an error.
Serialize a u128
value.
impl Serialize for u128 {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_u128(*self)
}
}
This method is available only on Rust compiler versions >=1.26. The default behavior unconditionally returns an error.
fn collect_seq<I>(self, iter: I) -> Result<Self::Ok, Self::Error> where
I: IntoIterator,
<I as IntoIterator>::Item: Serialize,
fn collect_seq<I>(self, iter: I) -> Result<Self::Ok, Self::Error> where
I: IntoIterator,
<I as IntoIterator>::Item: Serialize,
Collect an iterator as a sequence.
The default implementation serializes each item yielded by the iterator
using serialize_seq
. Implementors should not need to override this
method.
use serde::{Serialize, Serializer};
struct SecretlyOneHigher {
data: Vec<i32>,
}
impl Serialize for SecretlyOneHigher {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.collect_seq(self.data.iter().map(|x| x + 1))
}
}
fn collect_map<K, V, I>(self, iter: I) -> Result<Self::Ok, Self::Error> where
K: Serialize,
V: Serialize,
I: IntoIterator<Item = (K, V)>,
fn collect_map<K, V, I>(self, iter: I) -> Result<Self::Ok, Self::Error> where
K: Serialize,
V: Serialize,
I: IntoIterator<Item = (K, V)>,
Collect an iterator as a map.
The default implementation serializes each pair yielded by the iterator
using serialize_map
. Implementors should not need to override this
method.
use serde::{Serialize, Serializer};
use std::collections::BTreeSet;
struct MapToUnit {
keys: BTreeSet<i32>,
}
// Serializes as a map in which the values are all unit.
impl Serialize for MapToUnit {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.collect_map(self.keys.iter().map(|k| (k, ())))
}
}
Serialize a string produced by an implementation of Display
.
The default implementation builds a heap-allocated String
and
delegates to serialize_str
. Serializers are encouraged to provide a
more efficient implementation if possible.
use serde::{Serialize, Serializer};
impl Serialize for DateTime {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.collect_str(&format_args!("{:?}{:?}",
self.naive_local(),
self.offset()))
}
}
fn is_human_readable(&self) -> bool
fn is_human_readable(&self) -> bool
Determine whether Serialize
implementations should serialize in
human-readable form.
Some types have a human-readable form that may be somewhat expensive to construct, as well as a binary form that is compact and efficient. Generally text-based formats like JSON and YAML will prefer to use the human-readable one and binary formats like Postcard will prefer the compact one.
use serde::{Serialize, Serializer};
impl Serialize for Timestamp {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
if serializer.is_human_readable() {
// Serialize to a human-readable string "2015-05-15T17:01:00Z".
self.to_string().serialize(serializer)
} else {
// Serialize to a compact binary representation.
self.seconds_since_epoch().serialize(serializer)
}
}
}
The default implementation of this method returns true
. Data formats
may override this to false
to request a compact form for types that
support one. Note that modifying this method to change a format from
human-readable to compact or vice versa should be regarded as a breaking
change, as a value serialized in human-readable mode is not required to
deserialize from the same data in compact mode.
Implementations on Foreign Types
sourceimpl<'a, 'b> Serializer for &'a mut Formatter<'b>
impl<'a, 'b> Serializer for &'a mut Formatter<'b>
use serde::Serialize;
use std::fmt::{self, Display};
#[derive(Serialize)]
#[serde(rename_all = "kebab-case")]
pub enum MessageType {
StartRequest,
EndRequest,
}
impl Display for MessageType {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.serialize(f)
}
}