pub struct Empty;
Expand description

An empty field.

This can be used to indicate that the value of a field is not currently present but will be recorded later.

When a field’s value is Empty. it will not be recorded.

Trait Implementations§

Formats the value using the given formatter. 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.
Visits this value with the given Visitor.

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
TODO: once 1.33.0 is the minimum supported compiler version, remove Any::type_id_compat and use StdAny::type_id instead. https://github.com/rust-lang/rust/issues/27745
The archived version of the pointer metadata for this type.
Converts some archived metadata to the pointer metadata for itself.
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more
Deserializes using the given deserializer
Compare self to key and return true if they are equal.

Returns the argument unchanged.

Attaches the provided Context to this type, returning a WithContext wrapper. Read more
Attaches the current Context to this type, returning a WithContext wrapper. Read more
Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
Instruments this type with the current Span, returning an Instrumented wrapper. Read more
Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Calls U::from(self).

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

The alignment of pointer.
The type for initializers.
Initializes a with the given initializer. Read more
Dereferences the given pointer. Read more
Mutably dereferences the given pointer. Read more
Drops the object pointed to by the given pointer. Read more
The type for metadata in pointers and references to Self.
Should always be Self
The inverse inclusion map: attempts to construct self from the equivalent element of its superset. Read more
Checks if self is actually part of its subset T (and can be converted to it).
Use with care! Same as self.to_subset but without any property checks. Always succeeds.
The inclusion map: converts self to the equivalent element of its superset.
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.
upcast ref
upcast mut ref
upcast boxed dyn
Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more
Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more