Struct Value 

pub struct Value<'v>(/* private fields */);

An anonymous captured value that can be serialized or formatted.

Implementations

impl<'v> Value<'v>

pub fn capture_display(value: &'v (impl Display + 'static)) -> Value<'v>

Capture a displayable value.

pub fn from_display(value: &'v impl Display) -> Value<'v>

Get a displayable value.

This method can be used instead of Value::capture_display when the value can’t satisfy the 'static bound.

pub fn capture_debug(value: &'v (impl Debug + 'static)) -> Value<'v>

Capture a debuggable value.

pub fn from_debug(value: &'v impl Debug) -> Value<'v>

Get a debuggable value.

This method can be used instead of Value::capture_debug when the value can’t satisfy the 'static bound.

pub fn capture_serde(value: &'v (impl Serialize + 'static)) -> Value<'v>

Capture a serializable value.

pub fn from_serde(value: &'v impl Serialize) -> Value<'v>

Get a serializable value.

This method can be used instead of Value::capture_serde when the value can’t satisfy the 'static bound.

pub fn capture_sval(value: &'v (impl Value + 'static)) -> Value<'v>

Capture a serializable value.

pub fn from_sval(value: &'v impl Value) -> Value<'v>

Get a serializable value.

This method can be used instead of Value::capture_sval when the value can’t satisfy the 'static bound.

pub fn capture_error(value: &'v (impl Error + 'static)) -> Value<'v>

Capture an error.

pub fn from_any(value: &'v impl ToValue) -> Value<'v>

Capture a convertible type.

pub const fn null() -> Value<'v>

The absence of any meaningful value.

pub fn is_null(&self) -> bool

Whether the value is null.

pub fn by_ref<'b>(&'b self) -> Value<'b>

Get a new value, borrowing data from this one.

pub fn cast<'a, T>(self) -> Option<T>

where T: FromValue<'v>,

Attempt to convert this value into an owned instance of T.

This may involve downcasting, serializing, or parsing depending on the implementation of FromValue.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: 'static,

Attempt to downcast this value into a borrowed instance of T.

This method should be used as a potential optimization, but can’t be relied upon to always return Some. If any internal buffering happens between owned and borrowed value conversions then the internal captured type will change.

pub fn parse<T>(&self) -> Option<T>

where T: FromStr,

Attempt to parse an instance of T from this value.

If the value is an internally captured string then it will be parsed directly. If the value is not a string then it will be formatted into one and then parsed.

pub fn to_borrowed_str(&self) -> Option<&'v str>

Try get a borrowed string value.

pub fn to_borrowed_error(&self) -> Option<&'v (dyn Error + 'static)>

Try get a borrowed error value.

pub fn as_f64(&self) -> f64

Get a lossy binary floating point value.

If the value is numeric then it will be converted into an f64 using as conversions. If the value is not numeric then this method will attempt to parse an f64 from it. If the value can’t be parsed then f64::NAN is returned.

impl<'v> Value<'v>

pub fn to_f64_sequence(&self) -> Option<Vec<f64>>

Get a sequence of binary floating points from a captured sequence of values.

If the value is a sequence then Some is returned. Each element will be converted into a f64 in the same way as Value::as_f64. If the value is not a sequence then None is returned.

For more advanced or specific conversion cases, use serde or sval.

impl<'v> Value<'v>

pub fn to_owned(&self) -> OwnedValue

Get an owned value from this one.

pub fn to_shared(&self) -> OwnedValue

Get an owned value from this one, internally storing an Arc for cheap cloning.

pub fn to_cow_str(&self) -> Option<Cow<'v, str>>

Try get a string from this value.

If the value is a captured string then Some(Cow::Borrowed) will be returned. If the value is a string that needs to be buffered through a serialization framework then Some(Cow::Owned) is returned. In other cases None is returned.

Trait Implementations

impl<'v> Clone for Value<'v>

fn clone(&self) -> Value<'v>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'v> Debug for Value<'v>

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

Formats the value using the given formatter.

impl<'v> Display for Value<'v>

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

Formats the value using the given formatter.

impl<'v, 'a, const N: usize> From<&'v [&'a str; N]> for Value<'v>

fn from(value: &'v [&'a str; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [bool; N]> for Value<'v>

fn from(value: &'v [bool; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [f64; N]> for Value<'v>

fn from(value: &'v [f64; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [i128; N]> for Value<'v>

fn from(value: &'v [i128; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [i16; N]> for Value<'v>

fn from(value: &'v [i16; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [i32; N]> for Value<'v>

fn from(value: &'v [i32; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [i64; N]> for Value<'v>

fn from(value: &'v [i64; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [i8; N]> for Value<'v>

fn from(value: &'v [i8; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [isize; N]> for Value<'v>

fn from(value: &'v [isize; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [u128; N]> for Value<'v>

fn from(value: &'v [u128; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [u16; N]> for Value<'v>

fn from(value: &'v [u16; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [u32; N]> for Value<'v>

fn from(value: &'v [u32; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [u64; N]> for Value<'v>

fn from(value: &'v [u64; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [u8; N]> for Value<'v>

fn from(value: &'v [u8; N]) -> Value<'v>

Converts to this type from the input type.

impl<'v, const N: usize> From<&'v [usize; N]> for Value<'v>

fn from(value: &'v [usize; N]) -> Value<'v>

Converts to this type from the input type.

impl<'a, 'v> From<&'a Cow<'v, str>> for Value<'a>

fn from(value: &'a Cow<'v, str>) -> Value<'a>

Converts to this type from the input type.

impl<'a> From<&'a OwnedValue> for Value<'a>

fn from(value: &'a OwnedValue) -> Value<'a>

Converts to this type from the input type.

impl<'a> From<&'a String> for Value<'a>

fn from(value: &'a String) -> Value<'a>

Converts to this type from the input type.

impl<'v> From<&'v str> for Value<'v>

fn from(value: &'v str) -> Value<'v>

Converts to this type from the input type.

impl<'a, 'v> From<Option<&'a Cow<'v, str>>> for Value<'a>

fn from(value: Option<&'a Cow<'v, str>>) -> Value<'a>

Converts to this type from the input type.

impl<'a> From<Option<&'a String>> for Value<'a>

fn from(value: Option<&'a String>) -> Value<'a>

Converts to this type from the input type.

impl<'v> From<Option<&'v str>> for Value<'v>

fn from(value: Option<&'v str>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<bool>> for Value<'v>

fn from(value: Option<bool>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<f64>> for Value<'v>

fn from(value: Option<f64>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<i128>> for Value<'v>

fn from(value: Option<i128>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<i16>> for Value<'v>

fn from(value: Option<i16>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<i32>> for Value<'v>

fn from(value: Option<i32>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<i64>> for Value<'v>

fn from(value: Option<i64>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<i8>> for Value<'v>

fn from(value: Option<i8>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<isize>> for Value<'v>

fn from(value: Option<isize>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<u128>> for Value<'v>

fn from(value: Option<u128>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<u16>> for Value<'v>

fn from(value: Option<u16>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<u32>> for Value<'v>

fn from(value: Option<u32>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<u64>> for Value<'v>

fn from(value: Option<u64>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<u8>> for Value<'v>

fn from(value: Option<u8>) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<Option<usize>> for Value<'v>

fn from(value: Option<usize>) -> Value<'v>

Converts to this type from the input type.

impl<'a> From<Value<'a>> for OwnedValue

fn from(value: Value<'a>) -> OwnedValue

Converts to this type from the input type.

impl<'v> From<bool> for Value<'v>

fn from(value: bool) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<f64> for Value<'v>

fn from(value: f64) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<i128> for Value<'v>

fn from(value: i128) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<i16> for Value<'v>

fn from(value: i16) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<i32> for Value<'v>

fn from(value: i32) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<i64> for Value<'v>

fn from(value: i64) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<i8> for Value<'v>

fn from(value: i8) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<isize> for Value<'v>

fn from(value: isize) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<u128> for Value<'v>

fn from(value: u128) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<u16> for Value<'v>

fn from(value: u16) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<u32> for Value<'v>

fn from(value: u32) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<u64> for Value<'v>

fn from(value: u64) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<u8> for Value<'v>

fn from(value: u8) -> Value<'v>

Converts to this type from the input type.

impl<'v> From<usize> for Value<'v>

fn from(value: usize) -> Value<'v>

Converts to this type from the input type.

impl<'v> FromValue<'v> for Value<'v>

fn from_value(value: Value<'v>) -> Option<Value<'v>>

Perform the conversion.

impl<'v> Serialize for Value<'v>

Available on crate feature serde only.

fn serialize<S>( &self, serializer: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<'v> ToValue for Value<'v>

fn to_value(&self) -> Value<'_>

Perform the conversion.

impl<'v> Value for Value<'v>

Available on crate feature sval only.

fn stream<'sval, S>(&'sval self, stream: &mut S) -> Result<(), Error>

where S: Stream<'sval> + ?Sized,

Stream this value through a Stream.

fn tag(&self) -> Option<Tag>

Get the tag of this value, if there is one.

fn to_bool(&self) -> Option<bool>

Try convert this value into a boolean.

fn to_f32(&self) -> Option<f32>

Try convert this value into a 32bit binary floating point number.

fn to_f64(&self) -> Option<f64>

Try convert this value into a 64bit binary floating point number.

fn to_i8(&self) -> Option<i8>

Try convert this value into a signed 8bit integer.

fn to_i16(&self) -> Option<i16>

Try convert this value into a signed 16bit integer.

fn to_i32(&self) -> Option<i32>

Try convert this value into a signed 32bit integer.

fn to_i64(&self) -> Option<i64>

Try convert this value into a signed 64bit integer.

fn to_i128(&self) -> Option<i128>

Try convert this value into a signed 128bit integer.

fn to_u8(&self) -> Option<u8>

Try convert this value into an unsigned 8bit integer.

fn to_u16(&self) -> Option<u16>

Try convert this value into an unsigned 16bit integer.

fn to_u32(&self) -> Option<u32>

Try convert this value into an unsigned 32bit integer.

fn to_u64(&self) -> Option<u64>

Try convert this value into an unsigned 64bit integer.

fn to_u128(&self) -> Option<u128>

Try convert this value into an unsigned 128bit integer.

fn to_text(&self) -> Option<&str>

Try convert this value into a text string.

fn to_binary(&self) -> Option<&[u8]>

Try convert this value into a bitstring.

impl<'v> ValueRef<'v> for Value<'v>

Available on crate feature sval only.

fn stream_ref<S>(&self, stream: &mut S) -> Result<(), Error>

where S: Stream<'v> + ?Sized,

Stream this value through a Stream.