Remove garbage collected cache entries.
A caching proxy to the underlying ActivitySource.
A caching proxy to the underlying ActivitySource. Vars are cached by name, and are tracked with WeakReferences.
Produces an ActivitySource which queries this ActivitySource, falling back to a secondary ActivitySource only when the primary result is ActivitySource.Failed.
Produces an ActivitySource which queries this ActivitySource, falling back to a secondary ActivitySource only when the primary result is ActivitySource.Failed.
the secondary ActivitySource
A convenient wrapper for caching the results returned by the underlying ActivitySource.