Struct serde_json::Number

source · [−]
pub struct Number { /* private fields */ }
Expand description

Represents a JSON number, whether integer or floating point.

Implementations

Returns true if the Number is an integer between i64::MIN and i64::MAX.

For any Number 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());

Returns true if the Number is an integer between zero and u64::MAX.

For any Number 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());

Returns true if the Number can be represented by f64.

For any Number 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());

If the Number 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);

If the Number 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);

Represents the number 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));

Converts a finite f64 to a Number. Infinite or NaN values are not JSON numbers.

assert!(Number::from_f64(256.0).is_some());

assert!(Number::from_f64(f64::NAN).is_none());

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Deserialize this value from the given Serde deserializer. Read more

The error type that can be returned if some error occurs during deserialization. Read more

Require the Deserializer to figure out how to drive the visitor based on what data type is in the input. Read more

Hint that the Deserialize type is expecting an i8 value.

Hint that the Deserialize type is expecting an i16 value.

Hint that the Deserialize type is expecting an i32 value.

Hint that the Deserialize type is expecting an i64 value.

Hint that the Deserialize type is expecting a u8 value.

Hint that the Deserialize type is expecting a u16 value.

Hint that the Deserialize type is expecting a u32 value.

Hint that the Deserialize type is expecting a u64 value.

Hint that the Deserialize type is expecting a f32 value.

Hint that the Deserialize type is expecting a f64 value.

Hint that the Deserialize type is expecting an i128 value. Read more

Hint that the Deserialize type is expecting an u128 value. Read more

Hint that the Deserialize type is expecting a bool value.

Hint that the Deserialize type is expecting a char value.

Hint that the Deserialize type is expecting a string value and does not benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a string value and would benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a byte array and does not benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a byte array and would benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting an optional value. Read more

Hint that the Deserialize type is expecting a unit value.

Hint that the Deserialize type is expecting a unit struct with a particular name. Read more

Hint that the Deserialize type is expecting a newtype struct with a particular name. Read more

Hint that the Deserialize type is expecting a sequence of values.

Hint that the Deserialize type is expecting a sequence of values and knows how many values there are without looking at the serialized data. Read more

Hint that the Deserialize type is expecting a tuple struct with a particular name and number of fields. Read more

Hint that the Deserialize type is expecting a map of key-value pairs.

Hint that the Deserialize type is expecting a struct with a particular name and fields. Read more

Hint that the Deserialize type is expecting an enum value with a particular name and possible variants. Read more

Hint that the Deserialize type is expecting the name of a struct field or the discriminant of an enum variant. Read more

Hint that the Deserialize type needs to deserialize a value whose type doesn’t matter because it is ignored. Read more

Determine whether Deserialize implementations should expect to deserialize their human-readable form. Read more

The error type that can be returned if some error occurs during deserialization. Read more

Require the Deserializer to figure out how to drive the visitor based on what data type is in the input. Read more

Hint that the Deserialize type is expecting an i8 value.

Hint that the Deserialize type is expecting an i16 value.

Hint that the Deserialize type is expecting an i32 value.

Hint that the Deserialize type is expecting an i64 value.

Hint that the Deserialize type is expecting a u8 value.

Hint that the Deserialize type is expecting a u16 value.

Hint that the Deserialize type is expecting a u32 value.

Hint that the Deserialize type is expecting a u64 value.

Hint that the Deserialize type is expecting a f32 value.

Hint that the Deserialize type is expecting a f64 value.

Hint that the Deserialize type is expecting an i128 value. Read more

Hint that the Deserialize type is expecting an u128 value. Read more

Hint that the Deserialize type is expecting a bool value.

Hint that the Deserialize type is expecting a char value.

Hint that the Deserialize type is expecting a string value and does not benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a string value and would benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a byte array and does not benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting a byte array and would benefit from taking ownership of buffered data owned by the Deserializer. Read more

Hint that the Deserialize type is expecting an optional value. Read more

Hint that the Deserialize type is expecting a unit value.

Hint that the Deserialize type is expecting a unit struct with a particular name. Read more

Hint that the Deserialize type is expecting a newtype struct with a particular name. Read more

Hint that the Deserialize type is expecting a sequence of values.

Hint that the Deserialize type is expecting a sequence of values and knows how many values there are without looking at the serialized data. Read more

Hint that the Deserialize type is expecting a tuple struct with a particular name and number of fields. Read more

Hint that the Deserialize type is expecting a map of key-value pairs.

Hint that the Deserialize type is expecting a struct with a particular name and fields. Read more

Hint that the Deserialize type is expecting an enum value with a particular name and possible variants. Read more

Hint that the Deserialize type is expecting the name of a struct field or the discriminant of an enum variant. Read more

Hint that the Deserialize type needs to deserialize a value whose type doesn’t matter because it is ignored. Read more

Determine whether Deserialize implementations should expect to deserialize their human-readable form. Read more

Formats the value using the given formatter. Read more

Convert Number to Value

Examples
use serde_json::{Number, Value};

let n = Number::from(7);
let x: Value = n.into();

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

The associated error which can be returned from parsing.

Parses a string s to return a value of this type. Read more

Feeds this value into the given Hasher. Read more

Feeds a slice of this type into the given Hasher. Read more

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

This method tests for !=.

Serialize this value into the given Serde serializer. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Performs the conversion.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.