pub enum Value {
Null,
Bool(bool),
Number(Number),
String(String),
Array(Vec<Value>),
Object(Map<String, Value>),
}
Expand description
Represents any valid JSON value.
See the serde_json::value
module documentation for usage examples.
Variants§
Null
Represents a JSON null value.
let v = json!(null);
Bool(bool)
Represents a JSON boolean.
let v = json!(true);
Number(Number)
Represents a JSON number, whether integer or floating point.
let v = json!(12.5);
String(String)
Represents a JSON string.
let v = json!("a string");
Array(Vec<Value>)
Represents a JSON array.
let v = json!(["an", "array"]);
Object(Map<String, Value>)
Represents a JSON object.
By default the map is backed by a BTreeMap. Enable the preserve_order
feature of serde_json to use IndexMap instead, which preserves
entries in the order they are inserted into the map. In particular, this
allows JSON data to be deserialized into a Value and serialized to a
string while retaining the order of map keys in the input.
let v = json!({ "an": "object" });
Implementations§
Source§impl Value
impl Value
Sourcepub fn get<I: Index>(&self, index: I) -> Option<&Value>
pub fn get<I: Index>(&self, index: I) -> Option<&Value>
Index into a JSON array or map. A string index can be used to access a value in a map, and a usize index can be used to access an element of an array.
Returns None
if the type of self
does not match the type of the
index, for example if the index is a string and self
is an array or a
number. Also returns None
if the given key does not exist in the map
or the given index is not within the bounds of the array.
let object = json!({ "A": 65, "B": 66, "C": 67 });
assert_eq!(*object.get("A").unwrap(), json!(65));
let array = json!([ "A", "B", "C" ]);
assert_eq!(*array.get(2).unwrap(), json!("C"));
assert_eq!(array.get("A"), None);
Square brackets can also be used to index into a value in a more concise
way. This returns Value::Null
in cases where get
would have returned
None
.
let object = json!({
"A": ["a", "á", "à"],
"B": ["b", "b́"],
"C": ["c", "ć", "ć̣", "ḉ"],
});
assert_eq!(object["B"][0], json!("b"));
assert_eq!(object["D"], json!(null));
assert_eq!(object[0]["x"]["y"]["z"], json!(null));
Sourcepub fn get_mut<I: Index>(&mut self, index: I) -> Option<&mut Value>
pub fn get_mut<I: Index>(&mut self, index: I) -> Option<&mut Value>
Mutably index into a JSON array or map. A string index can be used to access a value in a map, and a usize index can be used to access an element of an array.
Returns None
if the type of self
does not match the type of the
index, for example if the index is a string and self
is an array or a
number. Also returns None
if the given key does not exist in the map
or the given index is not within the bounds of the array.
let mut object = json!({ "A": 65, "B": 66, "C": 67 });
*object.get_mut("A").unwrap() = json!(69);
let mut array = json!([ "A", "B", "C" ]);
*array.get_mut(2).unwrap() = json!("D");
Sourcepub fn is_object(&self) -> bool
pub fn is_object(&self) -> bool
Returns true if the Value
is an Object. Returns false otherwise.
For any Value on which is_object
returns true, as_object
and
as_object_mut
are guaranteed to return the map representation of the
object.
let obj = json!({ "a": { "nested": true }, "b": ["an", "array"] });
assert!(obj.is_object());
assert!(obj["a"].is_object());
// array, not an object
assert!(!obj["b"].is_object());
Sourcepub fn as_object(&self) -> Option<&Map<String, Value>>
pub fn as_object(&self) -> Option<&Map<String, Value>>
If the Value
is an Object, returns the associated Map. Returns None
otherwise.
let v = json!({ "a": { "nested": true }, "b": ["an", "array"] });
// The length of `{"nested": true}` is 1 entry.
assert_eq!(v["a"].as_object().unwrap().len(), 1);
// The array `["an", "array"]` is not an object.
assert_eq!(v["b"].as_object(), None);
Sourcepub fn as_object_mut(&mut self) -> Option<&mut Map<String, Value>>
pub fn as_object_mut(&mut self) -> Option<&mut Map<String, Value>>
If the Value
is an Object, returns the associated mutable Map.
Returns None otherwise.
let mut v = json!({ "a": { "nested": true } });
v["a"].as_object_mut().unwrap().clear();
assert_eq!(v, json!({ "a": {} }));
Sourcepub fn is_array(&self) -> bool
pub fn is_array(&self) -> bool
Returns true if the Value
is an Array. Returns false otherwise.
For any Value on which is_array
returns true, as_array
and
as_array_mut
are guaranteed to return the vector representing the
array.
let obj = json!({ "a": ["an", "array"], "b": { "an": "object" } });
assert!(obj["a"].is_array());
// an object, not an array
assert!(!obj["b"].is_array());
Sourcepub fn as_array(&self) -> Option<&Vec<Value>>
pub fn as_array(&self) -> Option<&Vec<Value>>
If the Value
is an Array, returns the associated vector. Returns None
otherwise.
let v = json!({ "a": ["an", "array"], "b": { "an": "object" } });
// The length of `["an", "array"]` is 2 elements.
assert_eq!(v["a"].as_array().unwrap().len(), 2);
// The object `{"an": "object"}` is not an array.
assert_eq!(v["b"].as_array(), None);
Sourcepub fn as_array_mut(&mut self) -> Option<&mut Vec<Value>>
pub fn as_array_mut(&mut self) -> Option<&mut Vec<Value>>
If the Value
is an Array, returns the associated mutable vector.
Returns None otherwise.
let mut v = json!({ "a": ["an", "array"] });
v["a"].as_array_mut().unwrap().clear();
assert_eq!(v, json!({ "a": [] }));
Sourcepub fn is_string(&self) -> bool
pub fn is_string(&self) -> bool
Returns true if the Value
is a String. Returns false otherwise.
For any Value on which is_string
returns true, as_str
is guaranteed
to return the string slice.
let v = json!({ "a": "some string", "b": false });
assert!(v["a"].is_string());
// The boolean `false` is not a string.
assert!(!v["b"].is_string());
Sourcepub fn as_str(&self) -> Option<&str>
pub fn as_str(&self) -> Option<&str>
If the Value
is a String, returns the associated str. Returns None
otherwise.
let v = json!({ "a": "some string", "b": false });
assert_eq!(v["a"].as_str(), Some("some string"));
// The boolean `false` is not a string.
assert_eq!(v["b"].as_str(), None);
// JSON values are printed in JSON representation, so strings are in quotes.
//
// The value is: "some string"
println!("The value is: {}", v["a"]);
// Rust strings are printed without quotes.
//
// The value is: some string
println!("The value is: {}", v["a"].as_str().unwrap());
Sourcepub fn is_number(&self) -> bool
pub fn is_number(&self) -> bool
Returns true if the Value
is a Number. Returns false otherwise.
let v = json!({ "a": 1, "b": "2" });
assert!(v["a"].is_number());
// The string `"2"` is a string, not a number.
assert!(!v["b"].is_number());
Sourcepub fn as_number(&self) -> Option<&Number>
pub fn as_number(&self) -> Option<&Number>
If the Value
is a Number, returns the associated Number
. Returns
None otherwise.
let v = json!({ "a": 1, "b": 2.2, "c": -3, "d": "4" });
assert_eq!(v["a"].as_number(), Some(&Number::from(1u64)));
assert_eq!(v["b"].as_number(), Some(&Number::from_f64(2.2).unwrap()));
assert_eq!(v["c"].as_number(), Some(&Number::from(-3i64)));
// The string `"4"` is not a number.
assert_eq!(v["d"].as_number(), None);
Sourcepub fn is_i64(&self) -> bool
pub fn is_i64(&self) -> bool
Returns true if the Value
is an integer between i64::MIN
and
i64::MAX
.
For any Value on which is_i64
returns true, as_i64
is guaranteed to
return the integer value.
let big = i64::max_value() as u64 + 10;
let v = json!({ "a": 64, "b": big, "c": 256.0 });
assert!(v["a"].is_i64());
// Greater than i64::MAX.
assert!(!v["b"].is_i64());
// Numbers with a decimal point are not considered integers.
assert!(!v["c"].is_i64());
Sourcepub fn is_u64(&self) -> bool
pub fn is_u64(&self) -> bool
Returns true if the Value
is an integer between zero and u64::MAX
.
For any Value on which is_u64
returns true, as_u64
is guaranteed to
return the integer value.
let v = json!({ "a": 64, "b": -64, "c": 256.0 });
assert!(v["a"].is_u64());
// Negative integer.
assert!(!v["b"].is_u64());
// Numbers with a decimal point are not considered integers.
assert!(!v["c"].is_u64());
Sourcepub fn is_f64(&self) -> bool
pub fn is_f64(&self) -> bool
Returns true if the Value
is a number that can be represented by f64.
For any Value on which is_f64
returns true, as_f64
is guaranteed to
return the floating point value.
Currently this function returns true if and only if both is_i64
and
is_u64
return false but this is not a guarantee in the future.
let v = json!({ "a": 256.0, "b": 64, "c": -64 });
assert!(v["a"].is_f64());
// Integers.
assert!(!v["b"].is_f64());
assert!(!v["c"].is_f64());
Sourcepub fn as_i64(&self) -> Option<i64>
pub fn as_i64(&self) -> Option<i64>
If the Value
is an integer, represent it as i64 if possible. Returns
None otherwise.
let big = i64::max_value() as u64 + 10;
let v = json!({ "a": 64, "b": big, "c": 256.0 });
assert_eq!(v["a"].as_i64(), Some(64));
assert_eq!(v["b"].as_i64(), None);
assert_eq!(v["c"].as_i64(), None);
Sourcepub fn as_u64(&self) -> Option<u64>
pub fn as_u64(&self) -> Option<u64>
If the Value
is an integer, represent it as u64 if possible. Returns
None otherwise.
let v = json!({ "a": 64, "b": -64, "c": 256.0 });
assert_eq!(v["a"].as_u64(), Some(64));
assert_eq!(v["b"].as_u64(), None);
assert_eq!(v["c"].as_u64(), None);
Sourcepub fn as_f64(&self) -> Option<f64>
pub fn as_f64(&self) -> Option<f64>
If the Value
is a number, represent it as f64 if possible. Returns
None otherwise.
let v = json!({ "a": 256.0, "b": 64, "c": -64 });
assert_eq!(v["a"].as_f64(), Some(256.0));
assert_eq!(v["b"].as_f64(), Some(64.0));
assert_eq!(v["c"].as_f64(), Some(-64.0));
Sourcepub fn is_boolean(&self) -> bool
pub fn is_boolean(&self) -> bool
Returns true if the Value
is a Boolean. Returns false otherwise.
For any Value on which is_boolean
returns true, as_bool
is
guaranteed to return the boolean value.
let v = json!({ "a": false, "b": "false" });
assert!(v["a"].is_boolean());
// The string `"false"` is a string, not a boolean.
assert!(!v["b"].is_boolean());
Sourcepub fn as_bool(&self) -> Option<bool>
pub fn as_bool(&self) -> Option<bool>
If the Value
is a Boolean, returns the associated bool. Returns None
otherwise.
let v = json!({ "a": false, "b": "false" });
assert_eq!(v["a"].as_bool(), Some(false));
// The string `"false"` is a string, not a boolean.
assert_eq!(v["b"].as_bool(), None);
Sourcepub fn is_null(&self) -> bool
pub fn is_null(&self) -> bool
Returns true if the Value
is a Null. Returns false otherwise.
For any Value on which is_null
returns true, as_null
is guaranteed
to return Some(())
.
let v = json!({ "a": null, "b": false });
assert!(v["a"].is_null());
// The boolean `false` is not null.
assert!(!v["b"].is_null());
Sourcepub fn as_null(&self) -> Option<()>
pub fn as_null(&self) -> Option<()>
If the Value
is a Null, returns (). Returns None otherwise.
let v = json!({ "a": null, "b": false });
assert_eq!(v["a"].as_null(), Some(()));
// The boolean `false` is not null.
assert_eq!(v["b"].as_null(), None);
Sourcepub fn pointer(&self, pointer: &str) -> Option<&Value>
pub fn pointer(&self, pointer: &str) -> Option<&Value>
Looks up a value by a JSON Pointer.
JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document.
A Pointer is a Unicode string with the reference tokens separated by /
.
Inside tokens /
is replaced by ~1
and ~
is replaced by ~0
. The
addressed value is returned and if there is no such value None
is
returned.
For more information read RFC6901.
§Examples
let data = json!({
"x": {
"y": ["z", "zz"]
}
});
assert_eq!(data.pointer("/x/y/1").unwrap(), &json!("zz"));
assert_eq!(data.pointer("/a/b/c"), None);
Sourcepub fn pointer_mut(&mut self, pointer: &str) -> Option<&mut Value>
pub fn pointer_mut(&mut self, pointer: &str) -> Option<&mut Value>
Looks up a value by a JSON Pointer and returns a mutable reference to that value.
JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document.
A Pointer is a Unicode string with the reference tokens separated by /
.
Inside tokens /
is replaced by ~1
and ~
is replaced by ~0
. The
addressed value is returned and if there is no such value None
is
returned.
For more information read RFC6901.
§Example of Use
use serde_json::Value;
fn main() {
let s = r#"{"x": 1.0, "y": 2.0}"#;
let mut value: Value = serde_json::from_str(s).unwrap();
// Check value using read-only pointer
assert_eq!(value.pointer("/x"), Some(&1.0.into()));
// Change value with direct assignment
*value.pointer_mut("/x").unwrap() = 1.5.into();
// Check that new value was written
assert_eq!(value.pointer("/x"), Some(&1.5.into()));
// Or change the value only if it exists
value.pointer_mut("/x").map(|v| *v = 1.5.into());
// "Steal" ownership of a value. Can replace with any valid Value.
let old_x = value.pointer_mut("/x").map(Value::take).unwrap();
assert_eq!(old_x, 1.5);
assert_eq!(value.pointer("/x").unwrap(), &Value::Null);
}
Trait Implementations§
Source§impl Default for Value
impl Default for Value
The default value is Value::Null
.
This is useful for handling omitted Value
fields when deserializing.
§Examples
use serde_json::Value;
#[derive(Deserialize)]
struct Settings {
level: i32,
#[serde(default)]
extras: Value,
}
let data = r#" { "level": 42 } "#;
let s: Settings = serde_json::from_str(data)?;
assert_eq!(s.level, 42);
assert_eq!(s.extras, Value::Null);
Source§impl<'de> Deserialize<'de> for Value
impl<'de> Deserialize<'de> for Value
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D: Deserializer<'de>,
fn deserialize<D>(deserializer: D) -> Result<Value, D::Error>where
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impl<'de> Deserializer<'de> for &'de Value
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type Error = Error
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V: Visitor<'de>,
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserializer
to figure out how to drive the visitor based
on what data type is in the input. Read moreSource§fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting an i8
value.Source§fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting an i16
value.Source§fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting an i32
value.Source§fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Error>where
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fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting an i64
value.Source§fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Error>where
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fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting a u8
value.Source§fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Error>where
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fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting a u16
value.Source§fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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V: Visitor<'de>,
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type is expecting a u32
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fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting a u64
value.Source§fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Error>where
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V: Visitor<'de>,
Deserialize
type is expecting a f32
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fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Error>where
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type is expecting a f64
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type is expecting an optional value. Read moreSource§fn deserialize_enum<V>(
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_enum<V>(
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
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self,
name: &'static str,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_newtype_struct<V>(
self,
name: &'static str,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a newtype struct with a
particular name.Source§fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a bool
value.Source§fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a char
value.Source§fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a string value and does
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. Read moreSource§fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Error>where
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V: Visitor<'de>,
Deserialize
type is expecting a string value and would
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fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting a byte array and does not
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V: Visitor<'de>,
fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a byte array and would
benefit from taking ownership of buffered data owned by the
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self,
_name: &'static str,
visitor: V,
) -> Result<V::Value, Error>where
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self,
_name: &'static str,
visitor: V,
) -> Result<V::Value, Error>where
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self,
_len: usize,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_tuple<V>(
self,
_len: usize,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
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type is expecting a sequence of values and
knows how many values there are without looking at the serialized data.Source§fn deserialize_tuple_struct<V>(
self,
_name: &'static str,
_len: usize,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_tuple_struct<V>(
self,
_name: &'static str,
_len: usize,
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type is expecting a tuple struct with a
particular name and number of fields.Source§fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
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self,
_name: &'static str,
_fields: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
fn deserialize_struct<V>(
self,
_name: &'static str,
_fields: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
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V: Visitor<'de>,
fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Error>where
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fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Error>where
V: Visitor<'de>,
Deserialize
type needs to deserialize a value whose type
doesn’t matter because it is ignored. Read moreSource§fn is_human_readable(&self) -> bool
fn is_human_readable(&self) -> bool
Deserialize
implementations should expect to
deserialize their human-readable form. Read moreSource§impl Display for Value
impl Display for Value
Source§fn fmt(&self, f: &mut Formatter<'_>) -> Result
fn fmt(&self, f: &mut Formatter<'_>) -> Result
Display a JSON value as a string.
let json = json!({ "city": "London", "street": "10 Downing Street" });
// Compact format:
//
// {"city":"London","street":"10 Downing Street"}
let compact = format!("{}", json);
assert_eq!(compact,
"{\"city\":\"London\",\"street\":\"10 Downing Street\"}");
// Pretty format:
//
// {
// "city": "London",
// "street": "10 Downing Street"
// }
let pretty = format!("{:#}", json);
assert_eq!(pretty,
"{\n \"city\": \"London\",\n \"street\": \"10 Downing Street\"\n}");
Source§impl<'a> From<Cow<'a, str>> for Value
impl<'a> From<Cow<'a, str>> for Value
Source§fn from(f: Cow<'a, str>) -> Self
fn from(f: Cow<'a, str>) -> Self
Convert copy-on-write string to Value::String
.
§Examples
use serde_json::Value;
use std::borrow::Cow;
let s: Cow<str> = Cow::Borrowed("lorem");
let x: Value = s.into();
use serde_json::Value;
use std::borrow::Cow;
let s: Cow<str> = Cow::Owned("lorem".to_string());
let x: Value = s.into();
Source§impl<T: Into<Value>> FromIterator<T> for Value
impl<T: Into<Value>> FromIterator<T> for Value
Source§fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self
fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self
Create a Value::Array
by collecting an iterator of array elements.
§Examples
use serde_json::Value;
let v = std::iter::repeat(42).take(5);
let x: Value = v.collect();
use serde_json::Value;
let v: Vec<_> = vec!["lorem", "ipsum", "dolor"];
let x: Value = v.into_iter().collect();
use std::iter::FromIterator;
use serde_json::Value;
let x: Value = Value::from_iter(vec!["lorem", "ipsum", "dolor"]);
Source§impl<I> Index<I> for Valuewhere
I: Index,
impl<I> Index<I> for Valuewhere
I: Index,
Source§fn index(&self, index: I) -> &Value
fn index(&self, index: I) -> &Value
Index into a serde_json::Value
using the syntax value[0]
or
value["k"]
.
Returns Value::Null
if the type of self
does not match the type of
the index, for example if the index is a string and self
is an array
or a number. Also returns Value::Null
if the given key does not exist
in the map or the given index is not within the bounds of the array.
For retrieving deeply nested values, you should have a look at the
Value::pointer
method.
§Examples
let data = json!({
"x": {
"y": ["z", "zz"]
}
});
assert_eq!(data["x"]["y"], json!(["z", "zz"]));
assert_eq!(data["x"]["y"][0], json!("z"));
assert_eq!(data["a"], json!(null)); // returns null for undefined values
assert_eq!(data["a"]["b"], json!(null)); // does not panic
Source§impl<I> IndexMut<I> for Valuewhere
I: Index,
impl<I> IndexMut<I> for Valuewhere
I: Index,
Source§fn index_mut(&mut self, index: I) -> &mut Value
fn index_mut(&mut self, index: I) -> &mut Value
Write into a serde_json::Value
using the syntax value[0] = ...
or
value["k"] = ...
.
If the index is a number, the value must be an array of length bigger than the index. Indexing into a value that is not an array or an array that is too small will panic.
If the index is a string, the value must be an object or null which is treated like an empty object. If the key is not already present in the object, it will be inserted with a value of null. Indexing into a value that is neither an object nor null will panic.
§Examples
let mut data = json!({ "x": 0 });
// replace an existing key
data["x"] = json!(1);
// insert a new key
data["y"] = json!([false, false, false]);
// replace an array value
data["y"][0] = json!(true);
// inserted a deeply nested key
data["a"]["b"]["c"]["d"] = json!(true);
println!("{}", data);
Source§impl<'de> IntoDeserializer<'de, Error> for &'de Value
impl<'de> IntoDeserializer<'de, Error> for &'de Value
Source§type Deserializer = &'de Value
type Deserializer = &'de Value
Source§fn into_deserializer(self) -> Self::Deserializer
fn into_deserializer(self) -> Self::Deserializer
Source§impl<'de> IntoDeserializer<'de, Error> for Value
impl<'de> IntoDeserializer<'de, Error> for Value
Source§type Deserializer = Value
type Deserializer = Value
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fn into_deserializer(self) -> Self::Deserializer
impl Eq for Value
impl StructuralPartialEq for Value
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T: Clone,
Source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)Source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
Source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
Source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.