The double spaced question mark expression in js is similar to the expression of A?B?C:D:E

After seeing the title, you might think, what kind of formula is this?

To be honest, I haven't found a direct answer to this question myself on the Internet.

This is what I encountered when I was debugging the js code, and I was puzzled for a long time, thinking that this is some syntax that I have never learned.

In fact, it is very simple. First of all, it can be disassembled like this: A? B? C: D : E

Let the longest part in the middle be F, then this formula can be written as: A?F:E

Typical C language ternary operator.

Let the value of this formula be equal to G,

Ner G = A?B?C:D:E;

Written into code is:

if(A==true)
{
    if(B==true)
    G = C;
    else
    G = D;
}
else
{
    G = E;
}
//G = A?B?C:D:E

参考资料：[Solved] Where do you put parentheses in the following javascript statement - CodeProject

If there is any mistake, please correct me, communicate politely, thank you very much.