Struct tracing_core::Field

source ·
pub struct Field { /* private fields */ }
Expand description

An opaque key allowing O(1) access to a field in a Span’s key-value data.

As keys are defined by the metadata of a span, rather than by an individual instance of a span, a key may be used to access the same field across all instances of a given span with the same metadata. Thus, when a subscriber observes a new span, it need only access a field by name once, and use the key for that name for all other accesses.

Implementations§

Returns an Identifier that uniquely identifies the Callsite which defines this field.

Returns a string representing the name of the field.

Trait Implementations§

Converts this type into a shared reference of the (usually inferred) input type.
Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Formats the value using the given formatter. 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 ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

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

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
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.