Struct tracing_core::span::Current

pub struct Current { /* private fields */ }

Indicates what the Subscriber considers the “current” span.

As subscribers may not track a notion of a current span, this has three possible states:

• “unknown”, indicating that the subscriber does not track a current span,
• “none”, indicating that the current context is known to not be in a span,
• “some”, with the current span’s Id and Metadata.

Implementations

impl Current

pub fn new(id: Id, metadata: &'static Metadata<'static>) -> Self

Constructs a new Current that indicates the current context is a span with the given metadata and metadata.

pub fn none() -> Self

Constructs a new Current that indicates the current context is not in a span.

pub fn is_known(&self) -> bool

Returns true if the Subscriber that constructed this Current tracks a current span.

If this returns true and id, metadata, or into_inner return None, that indicates that we are currently known to not be inside a span. If this returns false, those methods will also return None, but in this case, that is because the subscriber does not keep track of the currently-entered span.

pub fn into_inner(self) -> Option<(Id, &'static Metadata<'static>)>

Consumes self and returns the span Id and Metadata of the current span, if one exists and is known.

pub fn id(&self) -> Option<&Id>

Borrows the Id of the current span, if one exists and is known.

pub fn metadata(&self) -> Option<&'static Metadata<'static>>

Borrows the Metadata of the current span, if one exists and is known.

Trait Implementations

impl Debug for Current

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

Formats the value using the given formatter.

impl<'a> From<&'a Current> for Option<&'a Id>

fn from(cur: &'a Current) -> Self

Converts to this type from the input type.

impl<'a> From<&'a Current> for Option<&'static Metadata<'static>>

fn from(cur: &'a Current) -> Self

Converts to this type from the input type.

impl<'a> From<&'a Current> for Option<Id>

fn from(cur: &'a Current) -> Self

Converts to this type from the input type.

impl From<Current> for Option<Id>

fn from(cur: Current) -> Self

Converts to this type from the input type.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 24 bytes