AND multiple parameters

Use Array.prototype.every on all the passed arguments to check if they all are true;

function andMultipleExpr(...a) {
  if(a.length === 0) return false; // return false when no argument being passed
  return a.every(Boolean);
}

console.log(andMultipleExpr(true, true, false)); // should return false
console.log(andMultipleExpr(true, true, true)); // should return true

Early returns should make the code both more efficient and shorter:

function andMultipleExpr() {
  for (let i = 0; i < arguments.length; i++) {
    if (!arguments[i]) {
      return false;
    }
  }

  return true;
}

You need to

  1. Start out with logicalAnd set to true

  2. Use logicalAnd when updating it, rather than using two entries from arguments

The minimal change is:

function andMultipleExpr(){
    let logicalAnd = true; // ***
    let i;
    for (i = 0; i < arguments.length; i++){
        logicalAnd = logicalAnd && arguments[i]; // ***
    }
    return logicalAnd;
}
console.log(andMultipleExpr(true, true, false, false));

But mbojko's solution has the advantage of short-circuiting (stopping the loop when it first finds a falsy value), which seems like a good idea.

Since you're using ES2015+, you should probably use a rest parameter rather than arguments, and you can use a for-of loop:

function andMultipleExpr(...flags) {
    let logicalAnd = true;
    for (const flag of flags) {
        logicalAnd = logicalAnd && flag;
    }
    return logicalAnd;
}
console.log(andMultipleExpr(true, true, false, false));

You can also short-circuit that in keeping with mbojko's approach

function andMultipleExpr(...flags) {
    for (const flag of flags) {
        if (!flag) {
            return false;
        }
    }
    return true;
}
console.log(andMultipleExpr(true, true, false, false));

Some people might throw reduce at this, but Archie's every solution is much better. (But since your comparison isn't strict, I'd just make it .every(flag => flag).)

Tags:

Javascript

Function

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