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Built-in-like Range in JavaScript

Francesco Di Donato on October 06, 2021

Premise Make it possible to generate any range of integers with built-in-like syntax. Motivation? Honestly, none. Zero. Except for fun...
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Jon Randy 🎖️ • • Edited

I'm planning to build something similar, but with 'safe' monkey patching using Symbols. I think I'll end up with a syntax something like:

4[to](7) // [4, 5, 6, 7]
[ ...1[to](3), ...10[to](15) ] // [1, 2, 3, 10, 11, 12, 13, 14, 15]

(4)[to](7) // alternative way to write it
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Or maybe (not sure this is possible safely):

4[to(7)] // [4, 5, 6, 7]
[ ...1[to(3)], ...10[to(15)] ] // [1, 2, 3, 10, 11, 12, 13, 14, 15]
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Which syntax do you prefer? (I'm leaning towards the former)

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Jon Randy 🎖️ •

Could even expand it to:

1[to](19, {step: 2})) // [1, 3, 5, 7, 9, 11, 13, 15, 17, 19]
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etc.

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Francesco Di Donato • • Edited

It's an amazing idea, Jon. I find the second option more readable. Or, at least, it feels "righter". But I'm not sure it could work since a function cannot be used as a key in a plain object.
Anyway, I'd like to work on it, together. Would you like to?

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Jon Randy 🎖️ •

I already did a POC in about 5 lines of code - works perfectly

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Jon Randy 🎖️ •

Still trying to think of a way to make the second syntax work without unsafe monkey patching. I'm not sure it's possible. My POC uses the a[to](b) syntax. Basically, to is a method on the number prototype... nothing particularly fancy going on

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Jon Randy 🎖️ •

I think there is a way to do the 2nd syntax... I'll get back to you

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Jon Randy 🎖️ • • Edited

It works 👍 And it's safe

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Francesco Di Donato •

I'm glad to read it. If you like to share I'd love to see it!

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Jon Randy 🎖️ •

I noticed in your header image, you have (3)(7) - that's not gonna work

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Francesco Di Donato •

Ops, thank you man! This is what happens when you write posts at 2 a.m. :)
I'm gonna fix it

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Poker9x •

shshshsh

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Adam Crockett 🌀 •

This is too much magic for me, don't comment to argue, I don't like it I won't change my mind but you can like it.

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Francesco Di Donato •

Hi Adam, I understand you point of view. As I stated in the post, this is something superfluous, a dev can definitely live without it :)

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Adam Crockett 🌀 •

It's not that, I woke up on the wrong side of the bed and I saw prototype of native primitive type being modified and it's just not my bag. Sorry if this came across in any other way but grumpy 😜

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Francesco Di Donato •

Me too! Thank you!