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。

    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 });