sourceTextModule.createCachedData()


创建可与 SourceTextModule 构造函数的 cachedData 选项一起使用的代码缓存。 返回 Buffer。 在评估模块之前,可以多次调用此方法。

SourceTextModule 的代码缓存不包含任何 JavaScript 可观察状态。 代码缓存可以安全地与脚本源一起保存,并用于多次构造新的 SourceTextModule 实例。

SourceTextModule 源代码中的函数可以标记为延迟编译,并且在构建 SourceTextModule 时不会编译它们。 这些函数将在第一次调用时被编译。 代码缓存序列化 V8 目前知道的关于 SourceTextModule 的元数据,它可以用来加速未来的编译。

// 创建初始模块
const module = new vm.SourceTextModule('const a = 1;');

// 从这个模块创建缓存数据
const cachedData = module.createCachedData();

// 使用缓存数据创建新的模块。代码必须相同。
const module2 = new vm.SourceTextModule('const a = 1;', { cachedData });

Creates a code cache that can be used with the SourceTextModule constructor's cachedData option. Returns a Buffer. This method may be called any number of times before the module has been evaluated.

The code cache of the SourceTextModule doesn't contain any JavaScript observable states. The code cache is safe to be saved along side the script source and used to construct new SourceTextModule instances multiple times.

Functions in the SourceTextModule source can be marked as lazily compiled and they are not compiled at construction of the SourceTextModule. These functions are going to be compiled when they are invoked the first time. The code cache serializes the metadata that V8 currently knows about the SourceTextModule that it can use to speed up future compilations.

// Create an initial module
const module = new vm.SourceTextModule('const a = 1;');

// Create cached data from this module
const cachedData = module.createCachedData();

// Create a new module using the cached data. The code must be the same.
const module2 = new vm.SourceTextModule('const a = 1;', { cachedData });