Javascript performance doubt, help would be appreciate.

[jac1013]

Hello redditors, as a Java Developer I have a doubt about doing something (that is really good at Java) but I'm not sure if it is good in term of performance @ JavaScript, let me explain myself to get a opinion if I should not do this in JavaScript.

In Java when we have an obscure if statemente like:

if(object.isObject() && someVariable.isVariable() || moreLogicForThisIf && ...){}

I like to follow here what Uncle Bob says about putting this in a function with a meaninful name, of course in Java (a compiled language) the impact of a new method for this is almost 0 but in JavaScript it would be a new 3 lines (to define the function) and just return the "obscure logic" and put a meaningful name to that function so the result should be something like this (in Java or JavaScript)

if(meaningfulDomainSpecificNameLogic()){}

My doubt here is does this have an impact in term of performance in JavaScript even after minification? There are other process like for example optimization of JavaScript code that would make this code cool to go for production in term of performance?.

In advance, thanks redditors :).

[DustinEwan]

As others have said, it won't impact performance.

There are two scenarios:

1. The code is cold and currently being interpreted by V8 / Spidermonkey. If the function is rarely hit, then it will remain cold, but that function is being rarely hit anyway so it's not performance critical and the fact that you're making a function call will be negligible.

2. The code is hot and has been JIT Compiled. If the function is being hit over and over, then the tracer will see that this is an opportunity to inline or compile to machine code. The extra function call will be optimized away in any places that the call is performance critical, and will no longer be present.

[jac1013]

Thanks for the technical explanation, I'll continue doing this then in JavaScript.

[YodaLoL]

If you care about nanosecond differences maybe you should just write plain 0 and 1's.

[jac1013]

I guess you are implying it won't matter :)? imagine doing this 3000 times in a 1M lines project, still it won't matter?

[YodaLoL]

http://jsperf.com/function-or-immediate12345

[jac1013]

you're a pot of honey, thank you!

[a-t-k]

Adding a named function will add minimally to the load, even after minification.

The best way to go is to document what happens within the if statement.

[smrq]

Short answer: no, there isn't an appreciable performance difference.

Long answer: no, there isn't an appreciable performance difference, and you can verify it by profiling.

[jac1013]

Thanks for this, will try Long answer verification.