5
1

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?

More than 3 years have passed since last update.

【React】ReferenceError: Cannot access 'HogeState' before initializationの対処方法

Last updated at Posted at 2021-06-27

症状

reactでnpmstartしたとき、以下エラーメッセージが表示されました。 翻訳すると、「ReferenceError:初期化前に「HogeState」にアクセスできません」でした。
エラーメッセージ
Uncaught ReferenceError: Cannot access 'HogeState' before initialization
    at Hoge(Hoge.js:19)
    at renderWithHooks (react-dom.development.js:14985)
    at mountIndeterminateComponent (react-dom.development.js:17811)
    at beginWork (react-dom.development.js:19049)
    at HTMLUnknownElement.callCallback (react-dom.development.js:3945)
    at Object.invokeGuardedCallbackDev (react-dom.development.js:3994)
    at invokeGuardedCallback (react-dom.development.js:4056)
    at beginWork$1 (react-dom.development.js:23964)
    at performUnitOfWork (react-dom.development.js:22776)
    at workLoopSync (react-dom.development.js:22707)
    at renderRootSync (react-dom.development.js:22670)
    at performSyncWorkOnRoot (react-dom.development.js:22293)
    at scheduleUpdateOnFiber (react-dom.development.js:21881)
    at updateContainer (react-dom.development.js:25482)
    at react-dom.development.js:26021
    at unbatchedUpdates (react-dom.development.js:22431)
    at legacyRenderSubtreeIntoContainer (react-dom.development.js:26020)
    at Object.render (react-dom.development.js:26103)
    at Module.<anonymous> (index.js:7)
    at Module../src/index.js (index.js:18)
    at __webpack_require__ (bootstrap:856)
    at fn (bootstrap:150)
    at Object.1 (index.js:41)
    at __webpack_require__ (bootstrap:856)
    at checkDeferredModules (bootstrap:45)
    at Array.webpackJsonpCallback [as push] (bootstrap:32)
    at main.chunk.js:1

該当のファイルは以下になります。

Hoge.jsx
import React from "reacrt";

export const Hoge = () => {
   console.log(HogeState);
   const HogeState ~ "HOGE";
   return(
     <div>HogeState</div>
   )

}

解決方法

変数の宣言個所と参照個所を逆にすることで解決できました。 変数の宣言前にその変数を参照すると、このようなエラーが出るようです。
Hoge.jsx
import React from "reacrt";

export const Hoge = () => {
   const HogeState ~ "HOGE";
   console.log(HogeState);

   return(
     <div>HogeState</div>
   )

}

参考

5
1
0

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
5
1

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?