As we known, null has no property, we cannot get its existence, and if we access null.property, got an error, but not an undefined.
To consider the code below:
if (node.nextSibling.className == ...) {
...
}
If node is null, or node.nextSibling is null, the sentence will return error.
So the temporary solution is:
if ((node) && (next = node.nextSibling) && ... ) {
...
}
But if the depth is deeper, the conditional statement would be longer:
if (
(node) &&
(node.nextSibling) &&
(node.nextSibling.className == ...)
... ) {
...
}
The code would be ugly for a deep node.
To solve it, we can use a "trick" code like this:
if ( next = (node || 0).nextSibling) ) {
...
}
So the above code can be rewritten as:
if (((node || 0).nextSibling || 0).className == ...) {
...
}
Of course, this example should be suitable for personal development. If the project is maintained by many people, a framework is preferred.
