Single Var Pattern in Node, CommonJS

Question

In studying Node.js, I've found that most developers tend to not follow the single-var pattern for declaring variables. This also seems to be the case when declaring dependencies in CommonJS/Browserify.

Is there a technical advantage to having multiple var statements in Node and CommonJS compared to "regular" client-side JavaScript, or is it a matter of personal preference? If not, is there a reason why multiple var declarations are more prevalent?

Besides the well-known literature advocating the single-var pattern, the only data I've found on the subject is this jsperf showing better performance using a single declaration.

There's no reason why the practice should differ between server-side and client side code. It's just a matter of personal preference. — Peter Olson
– Peter Olson, Commented Jun 12, 2014 at 1:18
Watch this before you refer to the microbenchmarks next time: youtube.com/watch?v=65-RbBwZQdU :-) — zerkms
– zerkms, Commented Jun 12, 2014 at 1:20

Lucas T. · Accepted Answer · 2014-06-12 02:19:07Z

1

Crockford says that you should use the 'single var pattern', while Felix says otherwise.

I prefer to not use it, as it is more readable and easier to read. There are no technical advantages in any cases, just use the one you prefer.

answered Jun 12, 2014 at 2:19

Lucas T.

4065 silver badges18 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

cantera Over a year ago

Thanks - wasn't aware of any prominent Node coding styles. Would be nice if Felix explains why it's okay to deviate from Crockford (especially for declaring "deeper inside a function"), but that guide does seem pretty authoritative.

Lucas T. Over a year ago

"deeper inside a function"?

cantera Over a year ago

That quote is from the updated version: github.com/felixge/…

Lucas T. Over a year ago

Oh."deeper inside a function" is a reference to Crockford saying that you should only declare vars on the top of the scope, because of hoisting,while Felix says that you should put where it makes sense.

Zaenille · Accepted Answer · 2014-06-12 02:26:39Z

0

I think that in a case as small as this, Readability > Performance, especially when the performance increase is minimal.

Go with your preference. Personally, I like using multiple vars.

answered Jun 12, 2014 at 2:26

Zaenille

1,3849 silver badges17 bronze badges

Collectives™ on Stack Overflow

Single Var Pattern in Node, CommonJS

2 Answers 2

4 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related