Wonder why standard library doesn’t have binarySea...

# stdlib

[Eugen Martynov]

Wonder why standard library doesn’t have binarySearch variant for arrays?

[CLOVIS]

I guess it's because we're not supposed to use arrays that much 🤔

[Eugen Martynov]

I'm converting some java code that was written with the thought of the performance

[CLOVIS]

You may be interested in https://github.com/daniel-rusu/pods4k/blob/main/immutable-arrays/README.md
cc @Dan Rusu

[Dan Rusu]

Yeah, regular arrays are discouraged because they are mutable, lack proper equals/hashCode/toString, and aren't covariant.

Immutable Arrays address all those issues and also outperform regular arrays for many operations.

[Klitos Kyriacou]

If you're targeting JVM only, you can still use Java's binarySearch on arrays.

[Klitos Kyriacou]

If you're targeting multiple platforms, you can use Array<whatever>.asList() which wraps the original array and doesn't create boxed versions of each element, so you get to keep the memory efficiency, cache locality etc.

[Dan Rusu]

@Klitos Kyriacou, using asList() on a primitive array auto-boxes the values each time they are accessed because all the list operations operate on generics. So the asList() operation itself doesn't auto-box anything but all subsequent operations will.

[Eugen Martynov]

Thank you, people! I learned a lot

[Klitos Kyriacou]

@Dan Rusu yes, I realise that, but it only boxes one element at a time, instead of all elements. Thus, you don't get the typical 3-4 times memory usage increase that you would get if you used toList() instead of asList().