Struct serde_json::value::Number [−][src]
pub struct Number { /* fields omitted */ }
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));
Trait Implementations
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.
fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
Hint that the Deserialize
type is expecting a struct with a particular
name and fields. Read more
fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
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.
fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
Hint that the Deserialize
type is expecting a struct with a particular
name and fields. Read more
fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, Self::Error> where
V: Visitor<'de>,
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
Auto Trait Implementations
impl RefUnwindSafe for Number
impl UnwindSafe for Number
Blanket Implementations
Mutably borrows from an owned value. Read more