JavaScript a>0?0&&1?1:0:1;

Question

What does this tricky ternary operator mean? Why does it contain two question marks? I have found this code in a SL challenge and as a beginner in js, I would like to learn from it.

function f(a) {
return a>0?0&&1?1:0:1;
}
alert(f(1))

Answer 1

A ternary operator has a condition, if it evaluates to true then one after the ? is executed else one after the : is executed.

Divide it like this-

return a>0? { 0&&1?1:0 } :1;

If a>0 is true then the one inside the { } will execute and if it is false then it returns 1.

So 1>0 is true and inside { } again perform similar operation, so 0&&1 is false, so it will return 0.

Answer 2

So there is an embedded ternary operator in the outer one. Thanks Avinesh ~ swim ~ !