MeasurementInterpolation.swift

import Foundation

extension String.StringInterpolation {
    fileprivate static let myMeasurementFormatter: MeasurementFormatter = {
        let this = MeasurementFormatter()
        this.unitOptions = [.naturalScale]
        this.numberFormatter.maximumFractionDigits = 1
        return this
    }()
    mutating func appendInterpolation<UnitType>(_ measurement: Measurement<UnitType>) where UnitType: Unit {
        appendLiteral(Self.myMeasurementFormatter.string(from: measurement))
    }
}

let distance = Measurement(value: 123456.78, unit: UnitLength.meters)
let temperature = Measurement(value: 26.78, unit: UnitTemperature.celsius)
let area = Measurement(value: 1234567890.12, unit: UnitArea.squareMeters)

print("Locale: \(Locale.autoupdatingCurrent)")
print("Distance: \(distance)")
print("Temperature: \(temperature)")
print("Area: \(area)")

// Sample Output:
// Locale: en_US (autoupdatingCurrent)
// Distance: 76.7 mi
// Temperature: 80.2°F
// Area: 1,234.6 km²