Early exit from function?

Diving deeper: return

Return values matter! A return can send back any data type, not only undefined. Use this to communicate function results or status effectively:

function divide(x, y) {
  if (y === 0) return false; // Who divides by "0"? Not us!
  return x / y; // Otherwise, let's divide and conquer!
}
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Don't forget your return inside loops or nested functions to pop out:

function findFirstPositive(numbers) {
  for (let num of numbers) {
    if (num > 0) return num; // Found a good number, let's get out!
  }
  return null; // I've got nothing...
}


return is versatile, but can bring unexpected surprises if not used correctly. Many linters like JSHint can be told to scream if explicit returns are missing.

Leaving the party early: break, continue

Wanting to leave a block or loop instead of a function? Use break or continue with labelled loops:

outer: for (let i = 0; i < 10; i++) {
  for (let j = 0; j < 10; j++) {
    if (i + j >= 10) break outer; // Enough is enough!
  }
}
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For error kinda folks, throw can also end the function show-stoppingly:

function calculate(input) {
  if (!isValid(input)) {
    throw new Error('Invalid input'); // Well, I saw something shady...
  }
  // Further processing...
}
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And catch these divas using a neat little try-catch block:

try {
  result = calculate(data);
} catch (error) {
  console.error(error.message); // Let's handle it gracefully!
}
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Avoiding booby traps

For a smooth coder journey remember:

• Code readability first: Use multiple return to steer clear of nested if statements or to enhance clarity.
• Use guard clauses: Put conditional return at the start to take care of edge cases early and decisively.

Always weigh early exit's benefits against the function's objective and complexity.

Performance considerations

Function running on a large data set or looping over large arrays? Early return can prevent the engine from trending on Twitter:

function processItems(items) {
  if (!items.length) return; // Ssshh! No more code execution for empty array.
  // Heavy processing...
}


However, don't rush to optimize. Plan, profile, and measure for actual gains.

Coding it right

Coding is not just about getting it running. It's an art to cure chaos**. Balancing return usage with predictable function behavior and clean, maintainable code ensures your masterpiece is cherished by generations of developers!