通过Designated initializers初始化可以增强程序的可读性和可表达性 重载决议 假设我们有如下的测试用例 #include<iostream>#includestructPoint{/* data */inta_;intb_;};structPoint3{inta_;intb_;intc_;};voidfunc(Pointp){conststd::source_locationlocation=std::source_location::current();std::cout<<loca...
不过需要注意,为了享受这些“便利”,我们需要遵守一些规范,官方文档链接如下: Objective-C:Object Initialization,Multiple initializers Swift:Swift Initialization Swift和Objective-C略有不同,下面我们以Objective-C的规范为例。 1. 子类如果有指定初始化函数,那么指定初始化函数实现时必须调用它的直接父类的指定初始化函...
【C】C99的Designated Initializers特性 官方文档:http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html C99标准引入了Designated Initializers特性使得数组、结构体和联合体的初始化更加灵活和方便。 对于一个数组: int a[10] = { [1] = 1, [8 ... 9] = 10 }; 这样可以只初始化a[1], a[8], ...
As you can see, with designated initializers, we got a handy and usually more readable way of initializing aggregate types. The new technique is also common in other programming languages, like C or Python, so having it in C++ makes the programming experience even better. More in the paperP...
out-of-order designated initialization, nested designated initialization, mixing of designated initializers and regular initializers, and designated initialization of arrays are all supported in the C programming language, but are not allowed in C++. ...
The following example shows how the second and third membersbandcof structure variableklmare initialized with designated initializers: struct xyz { int a; int b; int c; } klm = { .a = 99, .c = 100 }; In the following example, the third and second elements of the one-dimensional array...
Initializers do not need to appear in order. The length of the array is the highest value specified plus one. Designated Initializers of a structure in C: In a structure initializer, specify the name of a field to initialize with‘.fieldname =’or‘fieldname:’before the element value. ...
Objective-C:Object Initialization,Multiple initializers Swift:Swift Initialization 指定初始化函数实现规范: 1. 子类如果有指定初始化函数,那么指定初始化函数实现时必须调用它的直接父类的指定初始化函数。 2. 如果子类有指定初始化函数,那么便利初始化函数必须调用自己的其它初始化函数(包括指定初始化函数以及其他的便...
non-trivial designated initializers解决办法 non-trivial designated initializers的问题通常是由于使用了较新的C语言标准,而编译器过旧,不支持该语法特性所致。解决该问题的方法如下: 1.升级编译器版本,使用支持该语法特性的编译器进行编译。 2.修改代码,去掉非关键部分的初始值,并将它们转移到代码中的其他位置。例如...
This attribute is used to mark managed constructors that bind Objective-C initializers marked with the NS_DESIGNATED_INITIALIZER attribute.