Question

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What does “options = options || {}” mean in Javascript?

I have seen this in JS:

item = item || {};

I’m guessing it’s some variation of a ternary operator but what does is actually do?

Answer 1

(expr1 || expr2)

“Returns expr1 if it can be converted to true; otherwise, returns
expr2.”

source

So when expr1 is (or evaluates to) one of these 0,"",false,null,undefined,NaN, then expr2 is returned, otherwise expr1 is returned