Enum Value 

pub enum Value {
    Null,
    Bool(bool),
    Num(f64),
    Str(String),
    List(Vec<Value>),
    Obj(BTreeMap<String, Value>),
}

A value the dialect computes over.

There is one numeric type, f64: every numeric literal and every JSON number widens to it, so 42 and 42.0 are the same value. The derived PartialEq is structural (for tests and round trips); the dialect’s own == — null == null, true != 1, NaN never equal — is Value::dialect_eq.

Variants

Null

Absent / unknown. Propagates through arithmetic and most functions.

Bool(bool)

A boolean — distinct from numbers: true == 1 is false.

Num(f64)

A number (always f64).

Str(String)

A string.

List(Vec<Value>)

A list of values.

Obj(BTreeMap<String, Value>)

A string-keyed object.

Implementations

impl Value

pub fn is_null(&self) -> bool

true for Null.

pub fn is_num(&self) -> bool

true for Num (never for Bool).

pub fn as_num(&self) -> Option<f64>

The number, if this is one.

pub fn as_bool(&self) -> Option<bool>

The boolean, if this is one.

pub fn as_str(&self) -> Option<&str>

The string, if this is one.

pub fn as_list(&self) -> Option<&[Value]>

The list, if this is one.

pub fn as_obj(&self) -> Option<&BTreeMap<String, Value>>

The object, if this is one.

pub fn type_name(&self) -> &'static str

The dialect’s name for this value’s type: null, boolean, number, string, list or object (what the typeOf function returns).

pub fn dialect_eq(&self, other: &Value) -> bool

The dialect’s ==: null == null is true; a boolean equals only the same boolean; any other comparison involving null is false; numbers compare by value (so NaN is never equal); lists and objects compare element-wise with these same rules.

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 Default for Value

fn default() -> Value

Returns the “default value” for a type.

impl Display for Value

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

The value as JSON text (a non-finite number prints as null).

impl From<&str> for Value

fn from(s: &str) -> Self

Converts to this type from the input type.

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

fn from(o: BTreeMap<String, Value>) -> Self

Converts to this type from the input type.

impl<T: Into<Value>> From<Option<T>> for Value

fn from(v: Option<T>) -> Self

Converts to this type from the input type.

impl From<String> for Value

fn from(s: String) -> Self

Converts to this type from the input type.

impl<T: Into<Value>> From<Vec<T>> for Value

fn from(v: Vec<T>) -> Self

Converts to this type from the input type.

impl From<bool> for Value

fn from(b: bool) -> Self

Converts to this type from the input type.

impl From<f64> for Value

fn from(n: f64) -> Self

Converts to this type from the input type.

impl From<i32> for Value

fn from(n: i32) -> Self

Converts to this type from the input type.

impl From<i64> for Value

fn from(n: i64) -> Self

Converts to this type from the input type.

impl PartialEq for Value

fn eq(&self, other: &Value) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Value