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How to explain JavaScript Closure to a 5 years old kid

Paper Coding on February 04, 2021

Lazy to read. Show me the code. // 👶 How to explain closure to a 5 years old kid /** * Closure is like a candy factory * You send the factory ...
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darkwiiplayer profile image
𒎏Wii 🏳️‍⚧️ • • Edited

Not that it matters for the purpose of the article, but I do have to nitpick a bit 😝

Why are you creating a new experts object with every call of the candyFactory function? That seems like unnecessary work for the garbage-collector.

Another minor issue is more easily explained with a simple snippet of code:

console.log(candyFactory('__proto__')(20))
// 20 __proto__ candies are made 
//                  by undefined.
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So yea, use new Map() isntead 😉

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Ranieri Althoff •

I don't think 5 year-olds are really into __proto__ candies

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Paper Coding •

Yeah we can move the experts out of the function, because it is a constant, and we should validate the input, but it is just a small example, so I took it easy. Thank for your suggestion.

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lionel-rowe •

It may be a little confusing to beginners if the only example given is one where there's no advantage to using a closure (the information-hiding aspect would be better served with a module). Maybe you could expand the article or write a sequel, with a second example that shows off the power and usefulness of closures as a feature.

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papercoding22 profile image
Paper Coding • • Edited

I am writing the next one, it will be more detailed and it will go with practical examples in real life project and open source. Thank for your suggestion

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Corentin Girard •

What would your solution for the __proto__ injection be? I didn't understand what you meant about new Map().

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darkwiiplayer profile image
𒎏Wii 🏳️‍⚧️ •

using a Map object instead of a plain JS object avoids the __proto__ problem

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abasyt • • Edited

Just ran into this today...

I just met you,
And this is crazy,
but here's my number (delegate)
So if something happens (event)
Call me maybe (callback)

Courtesy LightStriker and kindall on SO

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Log Boy •

It's neat, thank you for sharing !

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Pawan Pawar •

thanks for sharing !

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Elliot Wong •

Nice one Trung. More and more kids are learning how to code, this can come in handy whenever we meet one!

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Paper Coding •

Yeah, it also a way to help us to understand something deeper. Because “If you can't explain it simply, you don't understand it well enough.”
Albert Einstein

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Beck Lin •

Thanks for this amazing example !
I also have another question which might be off the topic here.
Under what circumstances will we leak the info in the closure ? I mean, if we don't use closure, which means we expose experts in the code, *how could this be unsafe or dangerous *? << I kept thinking about it for a long time

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spartan1cs •

very neat
Thanks!!

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Neth Insta •

thank for sharing

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Chapman •

Sit back and watch the five-year-olds complain about the candy. 😂