kakajika

extension Unicode.Scalar {
    var width: UInt32 {
        let code = self.value
        if (code >= 0 && code <= 128) {
            return 1
        } else {
            return 2
        }
    }
}

omochi

extension Array {    
    public mutating func remove(where: (Element) -> Bool) {
        while let index = self.index(where: `where`) {
            remove(at: index)
        }
    }
    
    public func removed(where: (Element) -> Bool) -> [Element] {
        var copy = self
        copy.remove(where: `where`)

omochi

extension Optional {    
    public mutating func ensure(_ f: () throws -> Wrapped) rethrows -> Wrapped {
        if let x = self {
            return x
        }
        
        let x = try f()
        self = x
        return x
    }

d-date

import Foundation

let intJson = #"{ "inUse": 1, "name": "Daiki Matsudate", "twitter": "d_date", "stars": 99999, "occupation": null}"#
let boolJson = #"{ "inUse": true, "name": "Daiki Matsudate", "twitter": "d_date", "stars": 99999, "occupation": null}"#

protocol Inherits {
    associatedtype SuperType

    var `super`: SuperType { get }
}