gistfile1.swift

//
//  DebugProperty.swift
//
//  Created by Mohamed Haddad
//

@propertyWrapper
internal struct DebugProperty<Value> {
    
    private var defaultValue: Value
    private var readOnly: Bool
    
    private var debugValue: Value
    private let description: String
    
    var wrappedValue: Value {
        get {
            #if DEBUG
                print("### [DEBUG] ### \(description)")
                return debugValue
            #else
                return defaultValue
            #endif
        }
        
        set {
            guard !readOnly else {
                assertionFailure("### [DEBUG] ### Debug properties are READ ONLY !")
                return
            }
            
            #if DEBUG
                debugValue = newValue
            #else
                defaultValue = newValue
            #endif
        }
    }
    
    init(wrappedValue: Value, defaultValue: Value, readOnly: Bool, debugDescription: String = "DebugPropertyWrapper") {
        self.debugValue = wrappedValue
        self.description = debugDescription
        self.defaultValue = defaultValue
        self.readOnly = readOnly
    }
}

#if DEBUG
@propertyWrapper
internal struct DebugOnlyProperty<Value> {
    
    private var debugValue: Value
    private let description: String
    private var readOnly: Bool
    
    var wrappedValue: Value {
        get {
            print("### [DEBUG] ### \(description)")
            return debugValue
        }
        
        set {
            guard !readOnly else {
                assertionFailure("### [DEBUG] ### Debug properties are READ ONLY !")
                return
            }
            debugValue = newValue
        }
    }
    
    init(wrappedValue: Value, readOnly: Bool, debugDescription: String = "DebugPropertyWrapper") {
        self.readOnly = readOnly
        self.debugValue = wrappedValue
        self.description = debugDescription
    }
}
#endif


/// useCase

@DebugOnlyProperty(readOnly: false)
static var myCrazyString: String? = nil

@DebugProperty(defaultValue: true, readOnly: true)
static var myCrazyBool: Bool = {
    return isEnabled
}()