ruin my life in javascript

Here are some ways you can unknowingly (or knowingly) ruin your life in javascript:

1. Using eval() to execute dynamic code. This is considered evil because it can execute potentially harmful code, leading to security vulnerabilities in your application.

index.tsx
let code = 'alert("Hello, world!")';
eval(code); // DO NOT DO THIS
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2. Failing to use const or let when declaring variables. This mistake can lead to unexpected variable mutations and bugs in your code.

index.tsx
var name = 'John';
name = 'Jane'; // Oops, name has been mutated
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3. Not handling errors properly. Failure to handle errors can cause your application to crash and result in unhappy users.

index.tsx
try {
  // some code
} catch(error) {
  console.log(error); // do NOT just log the error message and move on
}
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4. Using synchronous functions for network operations. This can cause your application to freeze and become unresponsive, frustrating your users.

index.tsx
xmlhttprequest.open('GET', '/api/data', false); // DO NOT set the third parameter to "false"
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5. Failing to sanitize user input. This can lead to security vulnerabilities such as cross-site scripting (XSS) attacks.

index.tsx
let userInput = '<script>alert("Hello, world!")</script>';
document.getElementById('output').innerHTML = userInput; // DO NOT do this
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In summary, be cautious and thoughtful when writing JavaScript code, and avoid these common mistakes that can ruin your life as a programmer.