Class Instance

web/src/runtime.ts:856–2336

 * - {@link detachFromCurrentScope}
 */
export class Instance implements Disposable {
  memory: Memory;
  exports: Record<string, Function>;
  cacheMetadata: Record<string, any> = {};
  private lib: FFILibrary;
  private env: Environment;
  private objFactory: Map<number, FObjectConstructor>;
  private ctx: RuntimeContext;
  private asyncifyHandler: AsyncifyHandler;
  private initProgressCallback: Array<InitProgressCallback> = [];
  private rng: LinearCongruentialGenerator;
  private deviceLostIsError = true;  // whether device.lost is due to actual error or dispose()
  private cacheState: CacheState = new CacheState();

  /**
   * Internal function(registered by the runtime)
   */
  private wasmCreateLibraryModule?: PackedFunc &
    ((getFunc: PackedFunc, getGlobal: PackedFunc) => PackedFunc);

  /**
   * Constructor
   *
   * importObject can also be a {@link LibraryProvider} object,
   * a WASI object, or an object containing wasmLibraryProvider field.
   *
   * @param wasmModule The input module or instance.
   * @param importObject The imports to initialize the wasmInstance if it is not provided.
   * @param wasmInstance Additional wasm instance argument for deferred construction.
   * @param env Directly specified environment module.
   *
   * @see Please use the async version {@link instantiate} when targeting browsers.
   */
  constructor(
    wasmModule: WebAssembly.Module,
    importObject: Record<string, any> = {},
    wasmInstance?: WebAssembly.Instance,
    env?: Environment
  ) {
    if (wasmInstance instanceof WebAssembly.Instance) {
      assert(
        env instanceof Environment,
        "env must be provided when passing in instance"
      );
    } else {
      assert(env === undefined);
      env = new Environment(importObject);
      wasmInstance = new WebAssembly.Instance(wasmModule, env.imports);
    }
    env.start(wasmInstance);
    this.env = env;
    this.lib = new FFILibrary(wasmInstance, env.imports);
    this.memory = this.lib.memory;
    this.exports = this.lib.exports;
    this.asyncifyHandler = new AsyncifyHandler(this.exports, this.memory.memory);
    this.objFactory = new Map<number, ObjectConstructor>();
    this.ctx = new RuntimeContext(
      (name: string) => {