### Building and Running NeverBounce Examples as JavaScript

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

These commands illustrate the process of compiling the TypeScript-based NeverBounce library into JavaScript and then executing a compiled example. `npm run build` compiles the project, and `node dist/examples/account-info.js` runs a specific JavaScript example from the compiled output directory.

```bash
# Build the project
npm run build

# Run an example (after compilation)
node dist/examples/account-info.js
```

--------------------------------

### Running NeverBounce Examples Directly with TypeScript

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

This command demonstrates how to execute a TypeScript example directly using the `npm run example` script, which typically leverages `ts-node`. This method bypasses the need for a separate compilation step, allowing for quicker execution of TypeScript examples.

```bash
npm run example examples/single-check.ts
```

--------------------------------

### Installing NeverBounce NodeJS Package

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

This command installs the NeverBounce NodeJS wrapper package using npm, saving it as a dependency in your project's `package.json` file. This is the standard way to add the library to your Node.js project.

```Bash
$ npm install neverbounce --save
```

--------------------------------

### Verifying Email with NeverBounce API using Async/Await in TypeScript

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

This example demonstrates how to initialize the NeverBounce client with an API key, perform an email verification check using `async/await`, and access detailed results including address and credit information. It also includes robust error handling for common API issues like authentication, referrer, and throttling errors.

```TypeScript
import NeverBounce from 'neverbounce';

// Initialize NeverBounce client
const client = new NeverBounce({apiKey: 'secret_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'});

// Verify an email with async/await
async function verifyEmail() {
  try {
    // You can request additional information like address_info and credits_info
    const result = await client.single.check('support@neverbounce.com', true, true);
    
    console.log('Result: ' + result.getResult()); // prints: "valid"
    console.log('Result (numeric): ' + result.getNumericResult());
    console.log('Is Valid? ' + result.is(NeverBounce.result.valid));
    
    // Access the response data with proper typing
    const response = result.getResponse();
    
    if (response.address_info) {
      console.log('Host: ' + response.address_info.host);
    }
    
    if (response.credits_info) {
      console.log('Free Credits Used: ' + response.credits_info.free_credits_used);
      console.log('Paid Credits Used: ' + response.credits_info.paid_credits_used);
    }
  } catch (err) {
    // Errors are thrown and can be caught to handle specific error types
    if (err instanceof Error) {
      switch(err.type) {
        case NeverBounce.errors.AuthError:
          // The API credentials used are bad, have you reset them recently?
          break;
        case NeverBounce.errors.BadReferrerError:
          // The script is being used from an unauthorized source, you may need to
          // adjust your app's settings to allow it to be used from here
          break;
        case NeverBounce.errors.ThrottleError:
          // Too many requests in a short amount of time, try again shortly or adjust
          // your rate limit settings for this application in the dashboard
          break;
        case NeverBounce.errors.GeneralError:
          // A non recoverable API error occurred check the message for details
          break;
        default:
          // Other non specific errors
          console.error('Error:', err.message);
          break;
      }
    } else {
      console.error('Unknown error:', err);
    }
  }
}

verifyEmail();
```

--------------------------------

### Setting NeverBounce API Key Environment Variable

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

This snippet shows the format for setting the `NEVERBOUNCE_API_KEY` environment variable in a `.env` file. This key is required for authenticating requests to the NeverBounce API. Users should replace the placeholder with their actual API key.

```plaintext
NEVERBOUNCE_API_KEY=secret_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
```

--------------------------------

### Verifying Email with NeverBounce API using Promises (TypeScript)

Source: https://github.com/neverbounce/neverbounceapi-nodejs/blob/master/README.md

This snippet demonstrates how to initialize the NeverBounce client and perform a single email verification using the Promise-based `then/catch` syntax. It shows how to access verification results, numeric results, check validity against NeverBounce constants, and properly handle various API errors with type checking. The `single.check` method takes the email, `address_info` flag, and `credits_info` flag as parameters.

```ts
import NeverBounce from 'neverbounce';

// Initialize NeverBounce client
const client = new NeverBounce({apiKey: 'secret_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'});

// Verify an email with Promise syntax
client.single.check('support@neverbounce.com', true, true)
  .then(result => {
    console.log('Result: ' + result.getResult()); // prints: "valid"
    console.log('Result (numeric): ' + result.getNumericResult());
    console.log('Is Valid? ' + result.is(NeverBounce.result.valid));
    
    // Access the response data with proper typing
    const response = result.getResponse();
    
    if (response.address_info) {
      console.log('Host: ' + response.address_info.host);
    }
  })
  .catch(err => {
    // Handle errors with type checking
    if (err instanceof Error) {
      switch(err.type) {
        case NeverBounce.errors.AuthError:
          console.error('Auth Error:', err.message);
          break;
        case NeverBounce.errors.BadReferrerError:
          console.error('Bad Referrer Error:', err.message);
          break;
        case NeverBounce.errors.ThrottleError:
          console.error('Throttle Error:', err.message);
          break;
        case NeverBounce.errors.GeneralError:
          console.error('General Error:', err.message);
          break;
        default:
          console.error('Error:', err.message);
          break;
      }
    } else {
      console.error('Unknown error:', err);
    }
  });
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.