Check out example codes for "react-native use typescript". It will help you in understanding the concepts better.

Code Example 1

{
  "compilerOptions": {
    "allowJs": true,
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true,
    "isolatedModules": true,
    "jsx": "react",
    "lib": ["es6"],
    "moduleResolution": "node",
    "noEmit": true,
    "strict": true,
    "target": "esnext"
  },
  "exclude": [
    "node_modules",
    "babel.config.js",
    "metro.config.js",
    "jest.config.js"
  ]
}

Code Example 2

yarn add --dev typescript @types/jest @types/react @types/react-native @types/react-test-renderer
# or for npm
npm install --save-dev typescript @types/jest @types/react @types/react-native @types/react-test-renderer

Code Example 3

module.exports = {
  preset: 'react-native',
  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node']
};

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