Babel 7 does not need ts-loader.

As of Babel 7 the ts-loader is unnecessary, because Babel 7 understands TypeScript. Complete details of a TypeScript + Babel7 + Webpack setup are here.

An overview of the set up without ts-loader.

Install Babel's TypeScript support. Only @babel/preset-typescript is mandatory; the other three add additional features that TypeScript supports.

npm install --save-dev @babel/preset-typescript npm install --save-dev @babel/preset-env npm install --save-dev @babel/plugin-proposal-class-properties npm install --save-dev @babel/plugin-proposal-object-rest-spread

Configure the additional .babelrc plugins and presets.

{    "presets": [        "@babel/preset-env",        "@babel/preset-typescript"    ],    "plugins": [        "@babel/proposal-class-properties",        "@babel/proposal-object-rest-spread"    ]}

And update your webpack.config.js (other code is omitted for clarity).

module: {  rules: [  {     test: /\.(js|jsx|tsx|ts)$/,     exclude: /node_modules/,     loader: 'babel-loader'    }  ]},resolve: {  extensions: ['*', '.js', '.jsx', '.tsx', '.ts'],},

Loaders always execute right to left, so changing to

test: /\.tsx?$/, loaders: ['babel-loader', 'ts-loader'], exclude: /node_modules/

Fixed the issue since it is going to run ts-loader first.

Full webpack.config.js file

module.exports = {  entry: ['babel-polyfill', './src/'],  output: {    path: __dirname,    filename: './dist/index.js',  },  resolve: {    extensions: ['', '.js', '.ts'],  },  module: {    loaders: [{      test: /\.ts$/, loaders: ['babel-loader', 'ts-loader'], exclude: /node_modules/    }],  }};

Sample project brunolm/typescript-babel-webpack

(4,32): error TS2304: Cannot find name 'regeneratorRuntime'.

This is a symptom that the output of babel is getting fed to ts. This order is wrong

Fix

You compilation setup should have TS output fed to Babel.

Alternatively you can compile TypeScript with just Babel using @babel/preset-typescript.

More

Compiling TypeScript with Babel : https://babeljs.io/docs/en/babel-preset-typescript