Math.min is capable of accepting multiple arguments, unlike functions such as parseInt. When using Math.min with reduce, the values like index and array are passed to it.
To demonstrate this concept, we can proxy Math.min by following these steps:
First, we create a proxy for Math.min:
var oldMath = Math.min;
Math.min = function (){
console.log(arguments)
return oldMath.apply(Math, arguments);
}
Then we execute the second version:
[-12, 57, 22, 12, -120, -3].reduce(Math.min);
This will output:
[-12, 57, 1, Array[6]]
As the last element in the array is not a number, the result becomes NaN
A similar example from MDN illustrates this point:
["1", "2", "3"].map(parseInt);
While one might expect [1, 2, 3], the actual result would be [1, NaN, NaN]
parseInt typically only uses one argument, but it actually takes two – the second being the radix. When used with Array.prototype.map, parseInt receives 3 arguments: the element, the index, and the array. While the third argument is disregarded, the second could lead to confusion due to how parseInt function interprets it.