Metalama//Commented Examples/Caching
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Example: caching

When optimizing performance, it is essential to store method outputs in memory to improve overall application efficiency, especially for time-consuming or computationally expensive tasks. Storing results in memory allows subsequent calls to quickly retrieve the data without having to re-execute the entire operation, reducing latency.

It is important to note that caching method outputs should only be applied to methods without side effects. Side effects are any changes made to the state of the system or external components resulting from method execution. Caching methods with side effects can cause unintended consequences that bypass necessary updates, modifications, or validations, resulting in stale or incorrect data. This can impact application stability and correctness. To ensure the application's stability and correctness, only cache the results of pure, deterministic functions that always produce the same output given the same input, without altering any external state.

Traditionally, caching the output of a method requires a lot of boilerplate code. However, this process can be significantly simplified by encapsulating it in an aspect.

One of the significant challenges of caching is generating a unique cache key reliably. In this article series, we present strategies for creating this key.

Article Description
Getting started Presents a first working version of the caching aspect.
Enforcing eligibility Makes the aspect report an error for void methods or methods with out or ref parameters.
Building the cache key Explains how to add a [CacheKeyMember] aspect to make the specified field or property part of the cache key for that type.
Supporting external types Shows how to build a caching key that includes external types.