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2 changes: 1 addition & 1 deletion docs/csharp/asynchronous-programming/async-return-types.md
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Expand Up @@ -71,7 +71,7 @@ The following example shows the behavior of an async event handler. In the examp

## Generalized async return types and ValueTask\<TResult\>

An async method can return any type that has an accessible `GetAwaiter` method that returns an instance of an *awaiter type*. In addition, the type returned from the `GetAwaiter` method must have the <xref:System.Runtime.CompilerServices.AsyncMethodBuilderAttribute?displayProperty=nameWithType> attribute. You can learn more in the article on [Attributes read by the compiler](../language-reference/attributes/general.md#asyncmethodbuilder-attribute) or the C# spec for the [Task type builder pattern](~/_csharpstandard/standard/classes.md#15142-task-type-builder-pattern).
An async method can return any type that has an accessible `GetAwaiter` method that returns an instance of an *awaiter type*. In addition, that type with a `GetAwaiter` method must have the <xref:System.Runtime.CompilerServices.AsyncMethodBuilderAttribute?displayProperty=nameWithType> attribute. You can learn more in the article on [Attributes read by the compiler](../language-reference/attributes/general.md#asyncmethodbuilder-attribute) or the C# spec for the [Task type builder pattern](~/_csharpstandard/standard/classes.md#15142-task-type-builder-pattern).

This feature is the complement to [awaitable expressions](~/_csharpstandard/standard/expressions.md#12982-awaitable-expressions), which describes the requirements for the operand of `await`. Generalized async return types enable the compiler to generate `async` methods that return different types. Generalized async return types enabled performance improvements in the .NET libraries. Because <xref:System.Threading.Tasks.Task> and <xref:System.Threading.Tasks.Task%601> are reference types, memory allocation in performance-critical paths, particularly when allocations occur in tight loops, can adversely affect performance. Support for generalized return types means that you can return a lightweight value type instead of a reference type to avoid more memory allocations.

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