Swift's formatting abilities are insanely good. I have created my own implementation of this formatting style not knowing that this API existed. I just learned about this yesterday (2023-02-26). Here's a fantastic resource all about Swift's formatting abilities: [Fucking Format Style](https://fuckingformatstyle.com/).

Twitter Likes Count Format with Swift's FormatStyle.swift

import Foundation

// This is so I didn't have to repeat myself for all of the for loops below.
extension FormatStyle where Self == IntegerFormatStyle<Int> {
    static func compactCount(significantDigits digits: Int = 3) -> Self {
        .number.precision(.significantDigits(digits)).notation(.compactName)
    }
}

// OR

let compact1 = number.formatted(.number.notation(.compactName))
let compact2 = number.formatted(.number.precision(.significantDigits(3)).notation(.compactName))

let likeCounts: [Int] = [
    37727,
    802,
    80382,
    9903293,
    7392083,
    39302292922,
    7839900222,
    892640238
]

// -------------------------------------------------------------

for number in likeCounts {
    print(number.formatted(.compactCount()))
}

/* PRINTS:
37.7K
802
80.4K
9.90M
7.39M
39.3B
7.84B
893M
*/

// -------------------------------------------------------------

for number in likeCounts {
    print(number.formatted(.compactCount(significantDigits: 0)))
}

/* PRINTS:
38K
802
80K
9.9M
7.4M
39B
7.8B
893M
*/

// -------------------------------------------------------------

for number in likeCounts {
    print(number.formatted(.compactCount(significantDigits: 1)))
}

/* PRINTS:
40K
800
80K
10M
7M
40B
8B
900M
*/

// -------------------------------------------------------------

for number in likeCounts {
    print(number.formatted(.compactCount(significantDigits: 4)))
}

/* PRINTS:
37.73K
802.0
80.38K
9.903M
7.392M
39.30B
7.840B
892.6M
*/