1.1 KiB
1.1 KiB
Enumerable.Empty<TResult> always returns cached instance
Scope
Edge
Version Introduced
4.5
Source Analyzer Status
Available
Change Description
Beginning in .NET 4.5, Enumerable.Empty always returns a cached internal instance IEnumerable<T>.
Previously, Enumerable.Empty would cache an empty IEnumerable<T> at the time the API was called, meaning that in some conditions in which Enumerable.Empty was called rapidly and concurrently, different instances of the type could be returned for different calls to the API.
- Quirked
- Build-time break
Recommended Action
Because the previous behavior was non-deterministic, code is unlikely to depend on it. However, in the unlikely case that empty enumerables are being compared and expected to sometimes be unequal, explicit empty arrays should be created (new T[0]) instead of using Enumerable.Empty.
Affected APIs
M:System.Linq.Enumerable.Empty``1
Category
LINQ