Make it so you can initialize arrays of a certain length

In regular TS/JS you can initialize arrays of a predefined length. This is useful for performance critical code where one can benefit from not resizing the dynamically-sized array several times. The single parameter is nice sugar we could easily integrate into the transpiler.

const strings = new Array<string>(12);

local strings = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

[Validark]

Firstly, avoiding 20 reallocations at run-time involving hundreds of thousands of elements being deleted and copied is more than “marginally faster”, although that is not the use-case or reason JS and Lua have shortcuts for these.

Lua has a built-in optimization for this that can initialize up to 50 nil values in an array at a time. That would probably be the maximum number of nil values you would ever want to put into a script in-line (or maybe 100 nil values, which would be 4 bytecode instructions). For insane cases where someone wants to allocate a million entries, we could either fallback on a for loop or just let Lua run that dynamically.

[evaera]

I think it should be noted that in regular JS/TS, presizing arrays does not actually allocate anything (all it does it set the length property) and in fact has the inverse effect and reduces the performance of the array significantly for as long as the object exists (even if it’s filled in later)