Struct json::number::Number

pub struct Number { /* fields omitted */ }

Number representation used inside JsonValue. You can easily convert the Number type into native Rust number types and back, or use the equality operator with another number type.

let foo: Number = 3.14.into();
let bar: f64 = foo.into();

assert_eq!(foo, 3.14);
assert_eq!(bar, 3.14);

More often than not you will deal with JsonValue::Number variant that wraps around this type, instead of using the methods here directly.

Methods

impl Number

fn from_parts(positive: bool, mantissa: u64, exponent: i16) -> Self

Construct a new Number from parts. This can't create a NaN value.

let pi = Number::from_parts(true, 3141592653589793, -15);

assert_eq!(pi, 3.141592653589793);

fn as_parts(&self) -> (bool, u64, i16)

Reverse to from_parts - obtain parts from an existing Number.

let pi = Number::from(3.141592653589793);
let (positive, mantissa, exponent) = pi.as_parts();

assert_eq!(positive, true);
assert_eq!(mantissa, 3141592653589793);
assert_eq!(exponent, -15);

fn is_sign_positive(&self) -> bool

fn is_zero(&self) -> bool

fn is_nan(&self) -> bool

fn is_empty(&self) -> bool

Test if the number is NaN or has a zero value.

fn as_fixed_point_u64(&self, point: u16) -> Option<u64>

Obtain an integer at a fixed decimal point. This is useful for converting monetary values and doing arithmetic on them without rounding errors introduced by floating point operations.

Will return None if Number is negative or a NaN.

let price_a = Number::from(5.99);
let price_b = Number::from(7);
let price_c = Number::from(10.2);

assert_eq!(price_a.as_fixed_point_u64(2), Some(599));
assert_eq!(price_b.as_fixed_point_u64(2), Some(700));
assert_eq!(price_c.as_fixed_point_u64(2), Some(1020));

fn as_fixed_point_i64(&self, point: u16) -> Option<i64>

Analog to as_fixed_point_u64, except returning a signed i64, properly handling negative numbers.

let balance_a = Number::from(-1.49);
let balance_b = Number::from(42);

assert_eq!(balance_a.as_fixed_point_i64(2), Some(-149));
assert_eq!(balance_b.as_fixed_point_i64(2), Some(4200));

Trait Implementations

impl PartialEq<JsonValue> for Number

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl Copy for Number

impl Clone for Number

fn clone(&self) -> Number

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Number

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl PartialEq for Number

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl Display for Number

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

Formats the value using the given formatter.

impl From<f64> for Number

fn from(float: f64) -> Number

Performs the conversion.

impl From<f32> for Number

fn from(float: f32) -> Number

Performs the conversion.

impl PartialEq<f64> for Number

fn eq(&self, other: &f64) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialEq<f32> for Number

fn eq(&self, other: &f32) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<isize> for Number

fn from(num: isize) -> Number

Performs the conversion.

impl PartialEq<isize> for Number

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<i8> for Number

fn from(num: i8) -> Number

Performs the conversion.

impl PartialEq<i8> for Number

fn eq(&self, other: &i8) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<i16> for Number

fn from(num: i16) -> Number

Performs the conversion.

impl PartialEq<i16> for Number

fn eq(&self, other: &i16) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<i32> for Number

fn from(num: i32) -> Number

Performs the conversion.

impl PartialEq<i32> for Number

fn eq(&self, other: &i32) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<i64> for Number

fn from(num: i64) -> Number

Performs the conversion.

impl PartialEq<i64> for Number

fn eq(&self, other: &i64) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<usize> for Number

fn from(num: usize) -> Number

Performs the conversion.

impl PartialEq<usize> for Number

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<u8> for Number

fn from(num: u8) -> Number

Performs the conversion.

impl PartialEq<u8> for Number

fn eq(&self, other: &u8) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<u16> for Number

fn from(num: u16) -> Number

Performs the conversion.

impl PartialEq<u16> for Number

fn eq(&self, other: &u16) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<u32> for Number

fn from(num: u32) -> Number

Performs the conversion.

impl PartialEq<u32> for Number

fn eq(&self, other: &u32) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl From<u64> for Number

fn from(num: u64) -> Number

Performs the conversion.

impl PartialEq<u64> for Number

fn eq(&self, other: &u64) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl Neg for Number

type Output = Number

The resulting type after applying the - operator

fn neg(self) -> Number

The method for the unary - operator