函数被调用多少次（偶数/奇数次）

Question

I am doing an exercise and depending on the number of times the function was called, a different result should be returned. If the function for example was called 0,1,2 times, it should return a number (see below), if it was called more than 3 times AND is odd (called 3 times, the third time called =odd) then it should return a string, etc. I know how I would do it if it was just called once or not at all, but I can't figure out how to write the code for odd/even times..

This part was provided and should NOT be changed:

var plus = function (a,b) {
    return a+b;
}
var func = sometimes(plus); 

var array = [];

for(var i = 0; i < 8; i++){
    array.push(func(2+i,3+i)) //should return [7,9,11, 'no idea']     
}

This is the function I wrote and is clearly wrong..

function sometimes (newFunc){
    var called = newFunc();
    if (called>4) {
        return newFunc;
    }
}

Answer 1

Not sure if this suits your issue, but give it a try running the code snippet below.

 var selfInvokeFunc = (function (func) { var counter = 0; return function (func) { if (counter >= 3 && counter % 2 != 0) { counter++; return "'no idea'"; } else { counter++; return func; } } })(); var plus = function (a,b) { return a+b; } var func = function (a, b) { return selfInvokeFunc(plus(a+1,b+1)); } var array = []; for(var i = 0; i < 8; i++){ array.push(func(2+i,3+i)); } alert(array); //should return [7,9,11,'no idea',15,'no idea',19,'no idea'] document.write(array);

That should return [7,9,11,'no idea',15,'no idea',19,'no idea'] whereas

array[0] = 7,

array[1] = 9,

array[2] = 11,

array[3] = 'no idea', //3rd times called

array[4] = 15,

array[5] = 'no idea', // Odd

array[6] = 19,

array[7] = 'no idea' // Odd

Hope it answers your question.