JavaScript：当 function 传入参数时，它返回 ``NaN```

Question

here is my code problem

function abc(num,x,y){
 return num * x + " " + num * y;
}

abc(5,2,4); //returns 10 20

abc(5,abc(5,6,6),4) //doesn't return 30 30 20 

I also want to know how to achieve if I call the function below (function inside the argument of the same function)-

abc(5,abc(abc(5,abc(5,6,6),abc(5,abc(5,6,6),4)))) // it must return something like how abc(5,abc(5,6,6),4) should return 30 30 20

I want when I call the function abc(5,2,abc(5,abc(5,4,4),3)) should return all parameter every time like 10 20 20 15 for calling the function - abc(5,2,abc(5,abc(5,4,4),3)) if I place the same function in the function Parameter/arguments.

I tried but when I call the function inside the same function arguments like abc(5,abc(5,6,6),4) the x in the function abc(num,x,y) becomes NaN hence returns like NaN 20 but not 30 30 20

---

if I do like

 function abc(num,x,y){
if(isNaN(x)){
return x + " " + y * num ;  //now it returns 30 30 20 for abc(5,abc(5,6,6),4)
}
 return num * x + " " + num * y;
}

but how to do for this abc(5,abc(abc(5,abc(5,6,6),abc(5,abc(5,6,6),4)))) to return the same way like above edited.

Answer 1

Your function abc(num,x,y) returns a string, which then cannot be used arithmetically in the next function.

Answer 2

Your function abc returns a string type which you are trying to multiply it with a number which will result into NaN, trying casting it with parseInt while calling abc and it should be fine.

function abc(num,x,y){
     return num * x + " " + num * y;
}
    
abc(5,2,4); //returns 10 20
    
abc(5,parseInt(abc(5,6,6)),4) // return "150 20"