valeurs falsies javascript
false //The keyword false.
0 //The Number zero (so, also 0.0, etc., and 0x0).
-0 //The Number negative zero (so, also -0.0, etc., and -0x0).
0n, -0n //The BigInt zero and negative zero (so, also 0x0n/-0x0n).
"", '', `` //Empty string value.
null //the absence of any value.
undefined //the primitive value.
NaN //not a number.
document.all
//Objects are falsy if and only if they have the [[IsHTMLDDA]] internal slot.
//That slot only exists in document.all and cannot be set using JavaScript.
Owlthegentleman