[Solved] Which block of code will execute faster? [closed]


The second one is always the better choice for readability, and the performance benefit (if one even exists) would be marginal using a switch statement. The < / > operators are probably an instruction or two of native code, and I can’t imagine that any switch statement would compile down to something so small.

I wouldn’t even bother to test the difference; it shouldn’t be worth your time unless you can prove that those few lines are the bottleneck in your program. (In which case, I would be exceedingly surprised.)

Also, if you’re really concerned about good performance practices you could cache the length and achieve a small readability win too.

if (this.id === 'username') {
  var length = this.value.length
  if (length < 3) {
    // 'Username must be at least 3 characters'
  } else if (length > 20) {
    // 'Username must be at most 20 characters'
  } else {
    // Another if else statement
  }
}

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solved Which block of code will execute faster? [closed]