AI solution for JavaScript Coding Question on BFE.dev
78. convert HEX color to RGBA

Here's one possible solution in JavaScript:

function hexToRgb(hex) {
  // Remove any leading "#" from the hex code
  hex = hex.replace(/^#/, '');

  // Validate the input: it should be either 3 or 6 hex digits
  if (!/^(?:[0-9a-fA-F]{3}){1,2}$/.test(hex)) {
    throw new Error('Invalid hex code');
  }

  // Convert a 3-digit hex code to a 6-digit one by duplicating each digit
  if (hex.length === 3) {
    hex = hex.split('').map(x => x + x).join('');
  }

  // Convert the hex code to RGB values (as integers)
  const r = parseInt(hex.substr(0, 2), 16);
  const g = parseInt(hex.substr(2, 2), 16);
  const b = parseInt(hex.substr(4, 2), 16);

  // Round the alpha value to 2 decimal places (if needed)
  const alpha = Math.round((1) * 100) / 100;

  // Return the RGB values as a functional notation string
  return `rgba(${r},${g},${b},${alpha})`;
}

Here's how you can use this function:

console.log(hexToRgb('#fff')); // 'rgba(255,255,255,1)'
console.log(hexToRgb('#00aaff')); // 'rgba(0,170,255,1)'
console.log(hexToRgb('#123abc')); // 'rgba(18,58,188,1)'
console.log(hexToRgb('#abc')); // Error: Invalid hex code
console.log(hexToRgb('#abc1234')); // Error: Invalid hex code