How to fix Module has no exported member 'X' in TypeScript

// In the source file (e.g., utils.ts), check exports:
export const formatDate = () => { /* ... */ };  // Named export
export default function helper() { /* ... */ }; // Default export
export { formatDate as format };                // Renamed export

// Common mistakes:
const notExported = () => { /* ... */ };        // NOT exported - can't import this
export { notExported };                         // Now it's exported

// SOURCE MODULE exports:
export const myFunction = () => {};      // Named export
export default class MyComponent {};     // Default export

// CORRECT imports:
import { myFunction } from "./module";   // Named import
import MyComponent from "./module";      // Default import (no braces)

// WRONG imports that cause TS2305:
import { MyComponent } from "./module";  // Trying named import for default export
import myFunction from "./module";       // Trying default import for named export

// Mixed imports (both default and named):
import MyComponent, { myFunction } from "./module";

// In module.ts:
export default mainFunction;
export const helper1 = () => {};
export const helper2 = () => {};

// Correct import:
import mainFunction, { helper1, helper2 } from "./module";

// In utils.ts:
export const formatDate = () => {};      // lowercase 'f', uppercase 'D'

// CORRECT:
import { formatDate } from "./utils";

// WRONG - various typos:
import { FormatDate } from "./utils";    // Wrong case
import { formatdate } from "./utils";    // Wrong case
import { formatDate } from "./utils";    // Typo in 'Date'
import { formateDate } from "./utils";   // Missing 't'

// Use IDE autocomplete to avoid typos:
// Type "format" and let VS Code suggest "formatDate"

# Check installed version
npm list package-name

# Check what version your package.json expects
cat package.json | grep "package-name"

# Compare with documentation
# Visit npmjs.com/package/package-name or GitHub releases

# Update to latest version (if compatible)
npm install package-name@latest

# Or install specific version
npm install [email protected]

# Many packages include migration guides
# Check GitHub releases or official docs

// WRONG - importing from wrong file
import { formatDate } from "./utils/index";  // Should be "./utils"

// CORRECT - check actual file structure
// Project structure:
// src/
//   utils/
//     index.ts    // Re-exports everything
//     date.ts     // Has formatDate export
//     string.ts   // Has other utilities

// In index.ts (re-export file):
export { formatDate } from "./date";
export { capitalize } from "./string";

// Now you can import from index:
import { formatDate, capitalize } from "./utils";

// Or import directly from date.ts:
import { formatDate } from "./utils/date";

// If ./components/index.ts doesn't export Button,
// but ./components/Button.ts does, you need:
import { Button } from "./components/Button";
// NOT:
import { Button } from "./components";  // Unless index.ts re-exports it

// If using third-party packages without types:
// Create a declaration file (e.g., types/custom.d.ts)
declare module "untyped-package" {
  export const someFunction: () => void;
  export interface Config { /* ... */ }
}

// Ensure tsconfig.json includes your declaration files:
{
  "compilerOptions": {
    "typeRoots": ["./node_modules/@types", "./types"]
  },
  "include": ["src/**/*", "types/**/*"]
}

# Generate declaration files to see exports
npx tsc --declaration --emitDeclarationOnly

# Or check node_modules for .d.ts files
find node_modules/package-name -name "*.d.ts"