re: short-circuits && clean code VIEW POST


It appears that it's a growing idiom in JS. It's likely adapted from the similar Perl idiom.

Neither JSLint nor JSHint like it.

I'm personally of two minds: it's super succinct and clever. Once you've see it once it's pretty obvious what's going on.

On the other hand, it is conflating expressions and statements. Turning an expression into flow-control.

I would use it in the same way I use in-line if blocks: only use if there's one statement and it all fits in one line. I probably wouldn't do this in a professional code base, but for my own stuff, sure.

In short, if it saves you an indent/block and can fit in one-line, it's okay. Other useful purposes are:

I like to read this as the "...if x AND then y" version of x && y

isWizard && hat = getPointyHat();
validInput || haltAndCatchFire(); // error validation, reads well "is validInput or error"
!valid && haltAndCatchFire(); // doesn't read as well but same logic

It should be used to make simple blocks that would otherwise be:

if (x) {
    z = y();

into just x && z = y();

It shouldn't be used to handle any significantly complex logic or statements.

I'd say keep it limited to things like argument validations.

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