为什么会出现此错误?
package.json
{
"name": "react-shopping",
"version": "0.1.0",
"private": true,
"dependencies": {
"@babel/core": "7.1.0",
"@svgr/webpack": "2.4.1",
"babel-core": "7.0.0-bridge.0",
"babel-eslint": "9.0.0",
"babel-jest": "23.6.0",
"babel-loader": "8.0.4",
"babel-plugin-named-asset-import": "^0.2.3",
"babel-preset-react-app": "^6.1.0",
"bfj": "6.1.1",
"case-sensitive-paths-webpack-plugin": "2.1.2",
"chalk": "2.4.1",
"css-loader": "1.0.0",
"dotenv": "6.0.0",
"dotenv-expand": "4.2.0",
"eslint": "5.6.0",
"eslint-config-react-app": "^3.0.5",
"eslint-loader": "2.1.1",
"eslint-plugin-flowtype": "2.50.1",
"eslint-plugin-import": "2.14.0",
"eslint-plugin-jsx-a11y": "6.1.2",
"eslint-plugin-react": "7.11.1",
"file-loader": "2.0.0",
"fork-ts-checker-webpack-plugin-alt": "0.4.14",
"fs-extra": "7.0.0",
"html-webpack-plugin": "4.0.0-alpha.2",
"identity-obj-proxy": "3.0.0",
"jest": "23.6.0",
"jest-pnp-resolver": "1.0.1",
"jest-resolve": "23.6.0",
"mini-css-extract-plugin": "0.4.3",
"optimize-css-assets-webpack-plugin": "5.0.1",
"pnp-webpack-plugin": "1.1.0",
"postcss-flexbugs-fixes": "4.1.0",
"postcss-loader": "3.0.0",
"postcss-preset-env": "6.0.6",
"postcss-safe-parser": "4.0.1",
"react": "^16.6.1",
"react-app-polyfill": "^0.1.3",
"react-dev-utils": "^6.1.1",
"react-dom": "^16.6.1",
"react-redux": "^5.1.1",
"redux": "^4.0.1",
"redux-logger": "^3.0.6",
"redux-thunk": "^2.3.0",
"resolve": "1.8.1",
"sass-loader": "7.1.0",
"style-loader": "0.23.0",
"terser-webpack-plugin": "1.1.0",
"url-loader": "1.1.1",
"webpack": "4.19.1",
"webpack-dev-server": "3.1.9",
"webpack-manifest-plugin": "2.0.4",
"workbox-webpack-plugin": "3.6.3"
},
"scripts": {
"start": "node scripts/start.js",
"build": "node scripts/build.js",
"test": "node scripts/test.js"
},
"eslintConfig": {
"extends": "react-app"
},
"browserslist": [
">0.2%",
"not dead",
"not ie <= 11",
"not op_mini all"
],
"jest": {
"collectCoverageFrom": [
"src/**/*.{js,jsx,ts,tsx}",
"!src/**/*.d.ts"
],
"resolver": "jest-pnp-resolver",
"setupFiles": [
"react-app-polyfill/jsdom"
],
"testMatch": [
"<rootDir>/src/**/__tests__/**/*.{js,jsx,ts,tsx}",
"<rootDir>/src/**/?(*.)(spec|test).{js,jsx,ts,tsx}"
],
"testEnvironment": "jsdom",
"testURL": "http://localhost",
"transform": {
"^.+\\.(js|jsx|ts|tsx)$": "<rootDir>/node_modules/babel-jest",
"^.+\\.css$": "<rootDir>/config/jest/cssTransform.js",
"^(?!.*\\.(js|jsx|ts|tsx|css|json)$)": "<rootDir>/config/jest/fileTransform.js"
},
"transformIgnorePatterns": [
"[/\\\\]node_modules[/\\\\].+\\.(js|jsx|ts|tsx)$",
"^.+\\.module\\.(css|sass|scss)$"
],
"moduleNameMapper": {
"^react-native$": "react-native-web",
"^.+\\.module\\.(css|sass|scss)$": "identity-obj-proxy"
},
"moduleFileExtensions": [
"web.js",
"js",
"web.ts",
"ts",
"web.tsx",
"tsx",
"json",
"web.jsx",
"jsx",
"node"
]
},
"babel": {
"presets": [
"react-app"
]
}
}
store.js
import {createStore} from 'redux';
function todos(state = [], action) {
switch (action.type) {
case 'ADD_TODO':
return state.concat([action.text]);
default:
return state;
}
}
const store = createStore(todos, ['Use Redux']);
store.dispatch({
type: 'ADD_TODO',
text: 'Read the docs'
});
console.log(store.getState());
App.js
import React, {Component} from 'react';
import './store';
class App extends Component {
render() {
return (
<div className="App">
<h1>asdas</h1>
</div>
);
}
}
export default App;
答案 0 :(得分:2)
在我看来,就像皮毛虫一样。当我删除两个空白行时,我没有得到任何错误:
import { createStore } from 'redux';
function todos(state = [], action) {
switch (action.type) {
case 'ADD_TODO':
return state.concat([action.text]);
default:
return state;
}
}
const store = createStore(todos, ['Use Redux']);
store.dispatch({
type: 'ADD_TODO',
text: 'Read the docs'
});
console.log(store.getState());