pub enum ViewState {
New,
NotNew,
}
Expand description
Indicates if this data instance has been seen (viewed).
For each instance (identified by the key), the middleware
internally maintains a view_state relative to each DataReader. The
view_state can either be NEW or NOT_NEW.
The view_state available in the SampleInfo is a snapshot of the view_state
of the instance relative to the DataReader used to access the samples at
the time the collection was obtained (i.e., at the time read or take was
called). The view_state is therefore the same for all samples in the
returned collection that refer to the same instance.
Once an instance has been detected as not having any “live” writers and
all the samples associated with the instance are ‘taken’ from the
DataReader, the middleware can reclaim all local resources regarding the
instance. Future samples will be treated as ‘never seen’.
Cf. SampleState
See DDS spec v.14 Section 2.2.2.5.1.8 Interpretation of the SampleInfo
view_state
indicates that either this is the first time that the DataReader has
ever accessed samples of that instance, or else that the DataReader
has accessed previous samples of the instance, but the instance has
since been reborn (i.e., become not-alive and then alive again).
indicates that the DataReader has already accessed samples of the same
instance and that the instance has not been reborn since
Set that contains all possible states
The resulting type after applying the &
operator.
Create a
BitFlags
with no flags set (in other words, with a value of 0).
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Create a
BitFlags
with all flags set.
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The resulting type after applying the |
operator.
The resulting type after applying the ^
operator.
Performs copy-assignment from
source
.
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Formats the value using the given formatter.
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The resulting type after applying the !
operator.
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.
The underlying integer type.
A value with no bits set.
The value used by the Default implementation. Equivalent to EMPTY, unless
customized.
A value with all flag bits set.
The name of the type for debug formatting purposes.
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Return the bits as a number type.
Immutably borrows from an owned value.
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Mutably borrows from an owned value.
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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.
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Uses borrowed data to replace owned data, usually by cloning.
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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.