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let someStringVar = someStringArray[4] ?? '';This is a https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_operatorUCyborg wrote: ↑2020-11-22, 01:53I recently came across some JavaScript code that looks like this:
Has anyone seen this before? UXP browsers don't seem to support it, but behavior seems the same as if "??" is replaced with "||".Code: Select all
let someStringVar = someStringArray[4] ?? '';
It appears to be a big pile of nothing to save a few keystrokes instead of typingContrary to the logical OR (||) operator, the left operand is returned if it is a falsy value which is not null or undefined. In other words, if you use || to provide some default value to another variable foo, you may encounter unexpected behaviors if you consider some falsy values as usable (eg. '' or 0). See below for more examples.
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let foo = (bar === undefined || bar === null) ? baz : bar