Enum Value

pub enum Value {
    Null,
    Boolean(bool),
    Number(Number),
    String(String),
    Array(Vec<Value>),
    Object(ValueMap),
}

JSON Value.

Variants

Null

Null value.

null

Boolean(bool)

A boolean value.

true

or

false

Number(Number)

An f64 or i64 number.

3.14159265358979

String(String)

A UTF-8 encoded string.

"The quick brown fox jumps over the lazy dog.\nhello, world"

The following characters must be escaped:

• \u{0}to \u{1f} (inclusive)
• \n (newline)
• \r (carriage return)
• \t (tab) (optional)
• "
• ' (optional)
• \
• / (optional)
• \u{8}
• \u{c}

Array(Vec<Value>)

An array of JSON Values.

[
    "hello, world",
    1234,
    3.14,
    true,
    false,
    null,
]

Object(ValueMap)

A Mapping of JSON Values by their name.

{
    "tag": null,
    "registered": true,
    "age": 197,
    "name": "Fred",
    "classes": [
        "Algebra",
        "History of Programming",
        "Algorithms and Datastructures",
        "Cryptography",
    ],
    "rgb_for_some_reason": {
        "r": 4,
        "g": 7
        "b": 3,
    }
}

Implementations

impl Value

pub fn pretty_print_format( &self, indent: Indent, spacing: bool, ) -> PrettyPrint<'_>

Returns an object suitable for pretty printing.

Arguments:

• indent: Controls the indentation. Use Indent::Spaces(0) if you don’t want indentation (This defeats the purpose of pretty printing).
• spacing: Determines whether or not there are spaces before and after colons.

pub fn pretty_print(&self) -> PrettyPrint<'_>

Returns the default pretty printer.

impl Value

pub fn push<T: Into<Value>>(&mut self, value: T)

Push value into a Value::Array. If the Value is Value::Null, convert it into a Value::Array and push value into it.

Panics if self Value is not Value::Null or Value::Array.

pub fn insert<T: Into<Value>, K: InsertKey>( &mut self, k: K, v: T, ) -> Option<Value>

Insert value into a Value::Object. If the Value is Value::Null, convert it into a Value::Array and insert value into it.

Panics if self Value is not Value::Null or Value::Array.

pub fn get<I: IndexOrKey>(&self, i_k: I) -> Option<&Value>

Get an immutable reference to a Value by index or key.

pub fn get_mut<I: IndexOrKey>(&mut self, i_k: I) -> Option<&mut Value>

Get a mutable reference to a Value by index or key.

pub fn len(&self) -> usize

Get the length of the Value if it is one of the following variants:

• Value::String
• Value::Array
• Value::Object

Trait Implementations

impl Clone for Value

fn clone(&self) -> Value

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Value

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Value

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&str> for Value

fn from(value: &str) -> Self

Create a Value from string.

impl From<HashMap<String, Value>> for Value

fn from(value: ValueMap) -> Self

Create a Value from a ValueMap. (hashbrown::HashMap when not preserve_order, indexmap::IndexMap when preserve_order)

impl From<String> for Value

fn from(value: String) -> Self

Create a Value from a String.

impl From<Vec<Value>> for Value

fn from(value: Vec<Value>) -> Self

Create a Value from a Vec

impl From<bool> for Value

fn from(value: bool) -> Self

Create a Value from a bool.

impl From<f64> for Value

fn from(value: f64) -> Self

Create a Value from an f64.

impl From<i64> for Value

fn from(value: i64) -> Self

Create a Value from an i64. Note that there is loss in precision because this value will be converted to f64.

impl FromStr for Value

fn from_str(s: &str) -> Result<Self, Self::Err>

Parse a JSON Value from a string.

type Err = ParseError

The associated error which can be returned from parsing.

impl<I: IndexOrKey> Index<I> for Value

type Output = Value

The returned type after indexing.

fn index(&self, index: I) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<I: IndexOrKey> IndexMut<I> for Value

fn index_mut(&mut self, index: I) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.