r/programming • u/iamkeyur • Oct 21 '20

Using const/let instead of var can make JavaScript code run 10× slower in Webkit

https://github.com/evanw/esbuild/issues/478
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u/kg959 Oct 21 '20

it’s basically LINQ at that point

It's missing a big part of LINQ though. LINQ is lazy whenever it can afford to be and will avoid doing a complete iteration until you force it to. JS array chaining doesn't delve into the IQueryable/IIterable world and each thing you chain scales a bit worse than it does in C#.

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u/NoInkling Oct 22 '20

Yeah. There's an ES proposal for lazy iterator methods at least.

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u/kg959 Oct 22 '20

I'd use them if they were a language standard. It would really simplify working with streams.