How to implement Singleton pattern in javascript since ES6 !

DI DIO Maximilien
May 6, 2018 · 1 min read

I would like to share my method to implement a singleton in javascript. To be clear with you, i like javascript since ES6 which brought lot of interesting features. (I think about the closure syntax with class keyword, an userfriendly syntax for java’s coders like me. This syntax is also helpful to implement lot of design pattern.

Pretty simple isn’t it ?

That’s why i love ES6, this singleton has the same structure as java’s version below.

I understand, the class syntax can be strange for javascript purists, but it’s very useful. You can se below, the previous syntax (ES5) to implement a javascript singleton.

So now, choose your your faction ! ES5 or ES6. Personnally, i’ve already chosen :)

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PS: With theses singletons i haven’t consider the concurrency issue caused by multi-thread use case. Be careful. (with node.js the usercode is single threaded, it means, you cannot have concurrency issue with singletons)


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