Enum rocket_contrib::Value
[−]
pub enum Value { Null, Bool(bool), Number(Number), String(String), Array(Vec<Value>), Object(Map<String, Value>), }
Represents any valid JSON value.
Variants
Null
Represents a JSON null value.
Bool(bool)
Represents a JSON boolean.
Number(Number)
Represents a JSON number, whether integer or floating point.
String(String)
Represents a JSON string.
Array(Vec<Value>)
Represents a JSON array.
Object(Map<String, Value>)
Represents a JSON object.
Methods
impl Value
fn get<I>(&self, index: I) -> Option<&Value> where
I: Index,
I: Index,
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));
fn get_mut<I>(&mut self, index: I) -> Option<&mut Value> where
I: Index,
I: Index,
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");
fn is_object(&self) -> bool
Returns true if the Value
is an Object. Returns false otherwise.
fn as_object(&self) -> Option<&Map<String, Value>>
If the Value
is an Object, returns the associated Map.
Returns None otherwise.
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.
fn is_array(&self) -> bool
Returns true if the Value
is an Array. Returns false otherwise.
fn as_array(&self) -> Option<&Vec<Value>>
If the Value
is an Array, returns the associated vector.
Returns None otherwise.
fn as_array_mut(&mut self) -> Option<&mut Vec<Value>>
If the Value
is an Array, returns the associated mutable vector.
Returns None otherwise.
fn is_string(&self) -> bool
Returns true if the Value
is a String. Returns false otherwise.
fn as_str(&self) -> Option<&str>
If the Value
is a String, returns the associated str.
Returns None otherwise.
fn is_number(&self) -> bool
Returns true if the Value
is a Number. Returns false otherwise.
fn is_i64(&self) -> bool
Returns true if the Value
is a number that can be represented by i64.
fn is_u64(&self) -> bool
Returns true if the Value
is a number that can be represented by u64.
fn is_f64(&self) -> bool
Returns true if the Value
is a number that can be represented by f64.
fn as_i64(&self) -> Option<i64>
If the Value
is a number, represent it as i64 if possible.
Returns None otherwise.
fn as_u64(&self) -> Option<u64>
If the Value
is a number, represent it as u64 if possible.
Returns None otherwise.
fn as_f64(&self) -> Option<f64>
If the Value
is a number, represent it as f64 if possible.
Returns None otherwise.
fn is_boolean(&self) -> bool
Returns true if the Value
is a Boolean. Returns false otherwise.
fn as_bool(&self) -> Option<bool>
If the Value
is a Boolean, returns the associated bool.
Returns None otherwise.
fn is_null(&self) -> bool
Returns true if the Value
is a Null. Returns false otherwise.
fn as_null(&self) -> Option<()>
If the Value
is a Null, returns ().
Returns None otherwise.
fn pointer(&'a self, pointer: &str) -> Option<&'a 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);
fn pointer_mut(&'a mut self, pointer: &str) -> Option<&'a 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
extern crate serde_json; use serde_json::Value; use std::mem; 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())); // "Steal" ownership of a value. Can replace with any valid Value. let old_x = value.pointer_mut("/x").map(|x| mem::replace(x, Value::Null)).unwrap(); assert_eq!(old_x, 1.5); assert_eq!(value.pointer("/x").unwrap(), &Value::Null); }
Trait Implementations
impl<I> IndexMut<I> for Value where
I: Index,
I: Index,
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);
impl PartialEq<str> for Value
impl<'a> PartialEq<&'a str> for Value
impl PartialEq<String> for Value
impl PartialEq<Value> for Value
impl PartialEq<i8> for Value
impl<'a> PartialEq<i8> for &'a Value
impl<'a> PartialEq<i8> for &'a mut Value
impl PartialEq<i16> for Value
impl<'a> PartialEq<i16> for &'a Value
impl<'a> PartialEq<i16> for &'a mut Value
impl PartialEq<i32> for Value
impl<'a> PartialEq<i32> for &'a Value
impl<'a> PartialEq<i32> for &'a mut Value
impl PartialEq<i64> for Value
impl<'a> PartialEq<i64> for &'a Value
impl<'a> PartialEq<i64> for &'a mut Value
impl PartialEq<isize> for Value
impl<'a> PartialEq<isize> for &'a Value
impl<'a> PartialEq<isize> for &'a mut Value
impl PartialEq<u8> for Value
impl<'a> PartialEq<u8> for &'a Value
impl<'a> PartialEq<u8> for &'a mut Value
impl PartialEq<u16> for Value
impl<'a> PartialEq<u16> for &'a Value
impl<'a> PartialEq<u16> for &'a mut Value
impl PartialEq<u32> for Value
impl<'a> PartialEq<u32> for &'a Value
impl<'a> PartialEq<u32> for &'a mut Value
impl PartialEq<u64> for Value
impl<'a> PartialEq<u64> for &'a Value
impl<'a> PartialEq<u64> for &'a mut Value
impl PartialEq<usize> for Value
impl<'a> PartialEq<usize> for &'a Value
impl<'a> PartialEq<usize> for &'a mut Value
impl PartialEq<f32> for Value
impl<'a> PartialEq<f32> for &'a Value
impl<'a> PartialEq<f32> for &'a mut Value
impl PartialEq<f64> for Value
impl<'a> PartialEq<f64> for &'a Value
impl<'a> PartialEq<f64> for &'a mut Value
impl Clone for Value
impl<I> Index<I> for Value where
I: Index,
I: Index,
type Output = 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
impl Serialize for Value
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
S: Serializer,
S: Serializer,
Serialize this value into the given Serde serializer. Read more
impl From<f32> for Value
fn from(f: f32) -> Value
Convert 32-bit floating point number to Value
Examples
use serde_json::Value; let f: f32 = 13.37; let x: Value = f.into();
impl From<f64> for Value
fn from(f: f64) -> Value
Convert 64-bit floating point number to Value
Examples
use serde_json::Value; let f: f64 = 13.37; let x: Value = f.into();
impl From<bool> for Value
impl From<String> for Value
fn from(f: String) -> Value
Convert String
to Value
Examples
use serde_json::Value; let s: String = "lorem".to_string(); let x: Value = s.into();
impl<'a> From<&'a str> for Value
fn from(f: &str) -> Value
Convert string slice to Value
Examples
use serde_json::Value; let s: &str = "lorem"; let x: Value = s.into();
impl<'a> From<Cow<'a, str>> for Value
fn from(f: Cow<'a, str>) -> Value
Convert copy-on-write string to Value
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();
impl From<Map<String, Value>> for Value
fn from(f: Map<String, Value>) -> Value
Convert map (with string keys) to Value
Examples
use serde_json::{Map, Value}; let mut m = Map::new(); m.insert("Lorem".to_string(), "ipsum".into()); let x: Value = m.into();
impl<T> From<Vec<T>> for Value where
T: Into<Value>,
T: Into<Value>,
fn from(f: Vec<T>) -> Value
Convert a Vec
to Value
Examples
use serde_json::Value; let v = vec!["lorem", "ipsum", "dolor"]; let x: Value = v.into();
impl<'a, T> From<&'a [T]> for Value where
T: Clone + Into<Value>,
T: Clone + Into<Value>,
fn from(f: &'a [T]) -> Value
Convert a slice to Value
Examples
use serde_json::Value; let v: &[&str] = &["lorem", "ipsum", "dolor"]; let x: Value = v.into();
impl From<i8> for Value
impl From<i16> for Value
impl From<i32> for Value
impl From<i64> for Value
impl From<isize> for Value
impl From<u8> for Value
impl From<u16> for Value
impl From<u32> for Value
impl From<u64> for Value
impl From<usize> for Value
impl Deserializer for Value
type Error = Error
fn deserialize<V>(self, visitor: V) -> Result<V::Value, Error> where
V: Visitor,
V: Visitor,
fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Error> where
V: Visitor,
V: Visitor,
fn deserialize_enum<V>(
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Error> where
V: Visitor,
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Error> where
V: Visitor,
fn deserialize_newtype_struct<V>(
self,
_name: &'static str,
visitor: V
) -> Result<V::Value, Value::Error> where
V: Visitor,
self,
_name: &'static str,
visitor: V
) -> Result<V::Value, Value::Error> where
V: Visitor,
fn deserialize_bool<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_u8<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_u16<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_u32<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_u64<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_i8<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_i16<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_i32<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_i64<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_f32<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_f64<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_char<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_str<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_string<__V>(
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_unit<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_seq<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_seq_fixed_size<__V>(
self,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_bytes<__V>(
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_byte_buf<__V>(
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_map<__V>(self, visitor: __V) -> Result<__V::Value, Value::Error> where
__V: Visitor,
__V: Visitor,
fn deserialize_unit_struct<__V>(
self,
&'static str,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
&'static str,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_tuple_struct<__V>(
self,
&'static str,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
&'static str,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_struct<__V>(
self,
&'static str,
&'static [&'static str],
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
&'static str,
&'static [&'static str],
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_struct_field<__V>(
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_tuple<__V>(
self,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
usize,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
fn deserialize_ignored_any<__V>(
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, Value::Error> where
__V: Visitor,
impl<'a> Deserializer for &'a Value
type Error = Error
fn deserialize<V>(self, visitor: V) -> Result<V::Value, Error> where
V: Visitor,
V: Visitor,
fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Error> where
V: Visitor,
V: Visitor,
fn deserialize_enum<V>(
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Error> where
V: Visitor,
self,
_name: &str,
_variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Error> where
V: Visitor,
fn deserialize_newtype_struct<V>(
self,
_name: &'static str,
visitor: V
) -> Result<V::Value, &'a Value::Error> where
V: Visitor,
self,
_name: &'static str,
visitor: V
) -> Result<V::Value, &'a Value::Error> where
V: Visitor,
fn deserialize_bool<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_u8<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_u16<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_u32<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_u64<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_i8<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_i16<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_i32<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_i64<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_f32<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_f64<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_char<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_str<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_string<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_unit<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_seq<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_seq_fixed_size<__V>(
self,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_bytes<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_byte_buf<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_map<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_unit_struct<__V>(
self,
&'static str,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
&'static str,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_tuple_struct<__V>(
self,
&'static str,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
&'static str,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_struct<__V>(
self,
&'static str,
&'static [&'static str],
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
&'static str,
&'static [&'static str],
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_struct_field<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_tuple<__V>(
self,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
usize,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
fn deserialize_ignored_any<__V>(
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
self,
visitor: __V
) -> Result<__V::Value, &'a Value::Error> where
__V: Visitor,
impl<T> FromIterator<T> for Value where
T: Into<Value>,
T: Into<Value>,
fn from_iter<I>(iter: I) -> Value where
I: IntoIterator<Item = T>,
I: IntoIterator<Item = T>,
Convert an iteratable type to a Value
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"]);
impl FromStr 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);
impl Debug for Value
fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>
Formats the value using the given formatter.
impl Display for Value
fn fmt(&self, f: &mut Formatter) -> Result<(), Error>
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}");
impl Deserialize for Value
fn deserialize<D>(deserializer: D) -> Result<Value, D::Error> where
D: Deserializer,
D: Deserializer,
Deserialize this value from the given Serde deserializer. Read more