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// Ensure that .d.ts files are created by tsc, but not .js files "declaration": true, "emitDeclarationOnly": true, // Ensure that Babel can safely transpile
//files in the TypeScript project
"compilerOptions": {
"isolatedModules": true
}
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npm install --save-dev typescript @babel/core @babel/cli @babel/plugin-proposal-class-properties @babel/preset-env @babel/preset-typescript