feature wrapper might return null

leyhline · Jun 22, 2023 · 55612dd · 55612dd
1 parent dbbcf11
commit 55612dd
Show file tree

Hide file tree

Showing 3 changed files with 10 additions and 18 deletions.
diff --git a/src/Dictionary.ts b/src/Dictionary.ts
@@ -1,7 +1,7 @@
 export interface Dictionary<T extends Features = Record<string, never>> {
   url: string;
   cacheName: string;
-  wrapper?: (feature: string[]) => T;
+  wrapper?: (feature: string[]) => T | null;
 }
 
 export const UNIDIC2: Dictionary<UnidicFeature26> = {
@@ -28,12 +28,8 @@ export const JUMANDIC: Dictionary = {
 
 export type Features = { [key: string]: string };
 
-function createUnidicFeature26(features: string[]): UnidicFeature26 {
-  const numberOfFields = 26;
-  console.assert(
-    features.length === numberOfFields,
-    `Invalid feature length, expected ${numberOfFields}, got ${features.length}`
-  );
+function createUnidicFeature26(features: string[]): UnidicFeature26 | null {
+  if (features.length !== 26) return null;
   return {
     pos1: features[0],
     pos2: features[1],
@@ -93,12 +89,8 @@ export interface UnidicFeature26 extends Features {
   aModType: string;
 }
 
-function createUnidicFeature29(features: string[]): UnidicFeature29 {
-  const numberOfFields = 29;
-  console.assert(
-    features.length === numberOfFields,
-    `Invalid feature length, expected ${numberOfFields}, got ${features.length}`
-  );
+function createUnidicFeature29(features: string[]): UnidicFeature29 | null {
+  if (features.length !== 29) return null;
   return {
     pos1: features[0],
     pos2: features[1],

diff --git a/src/MecabWorker.ts b/src/MecabWorker.ts
@@ -89,11 +89,11 @@ interface MecabWorkerOptions {
  * @example
  * const worker = await MecabWorker.create(UNIDIC3)
  * const result = await worker.parse('青森県と秋田県にまたがり所在する十和田湖、御鼻部山展望台からの展望')
- * console.log(result)
+ * const nodes = await worker.parseToNodes('青森県と秋田県にまたがり所在する十和田湖、御鼻部山展望台からの展望')
  */
 export class MecabWorker<T extends Features = Record<string, never>> {
   private worker: Worker;
-  private wrapper?: (feature: string[]) => T;
+  private wrapper?: (feature: string[]) => T | null;
   /**
    * Helper function to call `MecabWorker.init` after construction.
    */
@@ -105,7 +105,7 @@ export class MecabWorker<T extends Features = Record<string, never>> {
     return mecabWorker.init(dictionary, options).then(() => mecabWorker);
   }
 
-  constructor(wrapper?: (feature: string[]) => T) {
+  constructor(wrapper?: (feature: string[]) => T | null) {
     if (!testModuleWorkerSupport()) {
       throw new Error(
         "Cannot initialize MeCab. Module workers are not supported in your browser."
@@ -188,7 +188,7 @@ export class MecabWorker<T extends Features = Record<string, never>> {
 }
 
 /**
- * Link to stackoverflow
+ * https://stackoverflow.com/questions/62954570/javascript-feature-detect-module-support-for-web-workers
  */
 function testModuleWorkerSupport(): boolean {
   let supports = false;

diff --git a/src/mecab-worker.ts b/src/mecab-worker.ts
@@ -166,7 +166,7 @@ class MecabNode<T extends Features = Record<string, never>> {
   readonly stat: Stat;
 
   features: string[] = [];
-  feature: T = {} as T;
+  feature: T | null = null;
 
   constructor(Module: Module, nodePtr: number) {
     this.nextPtr = Module.getValue(nodePtr + this.nextPtrOffset, "*");