https://gist.github.com/ktanaka117/7b4297df110d3e40722100badca9a0ae ←の汎用形

ModernInitializerGeneral.swift

import UIKit

public struct Maker<Product> {
    let product: Product
}

extension Maker where Product: UILabel {
    public func set(textColor color: UIColor) -> Maker {
        self.product.textColor = color
        return self
    }
    
    public func set(numberOfLines number: Int) -> Maker {
        self.product.numberOfLines = number
        return self
    }
    
    public func set(textAlignment alignment: NSTextAlignment) -> Maker {
        self.product.textAlignment = alignment
        return self
    }
    
    public func set(lineBreakMode mode: NSLineBreakMode) -> Maker {
        self.product.lineBreakMode = mode
        return self
    }
    
    public func set(font: UIFont) -> Maker {
        self.product.font = font
        return self
    }
}

extension UILabel {
    public static func make(frame: CGRect = .zero, by making: (Maker<UILabel>) -> Maker<UILabel>) -> UILabel {
        let product = UILabel(frame: frame)
        let maker = Maker<UILabel>(product: product)
        let resultMaker = making(maker)
        let resultProduct = resultMaker.product
        
        return resultProduct
    }
}

let label = UILabel.make(frame: .zero) { $0
    .set(textColor: .red)
    .set(numberOfLines: 0)
    .set(textAlignment: .center)
    .set(lineBreakMode: .byWordWrapping)
    .set(font: .systemFont(ofSize: 20))
}