In the Introduction to Swift WWDC session, a read-only property description is demonstrated: class Vehicle { var numberOfWheels = 0 var description: String { return "\(numberOfWheels) wheels" } } let vehicle = Vehicle() println(vehicle.descripti…
In addition to stored properties, classes, structures, and enumerations can define computed properties, which do not actually store a value. Instead, they provide a getter and an optional setter to retrieve and set other properties and values indirec…
[Computed property names] That allows you to put an expression in brackets [], that will be computed as the property name. 参考:https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Operators/Object_initializer#Computed_property_names…
一.函数类型 Every function in Swift has a type, consisting of the function’s parameter types and return type. Function Types Every function has a specific function type, made up of the parameter types and the return type of the function. For example: func…
Arrow Function.md Arrow Functions The basic syntax of an arrow function is as follows var fn = data => data; The code means : var fn = function( data ) { return data; } let getNumber = () => 42; console.log(typeof getNumber); console.log(getNumber()…
https://docs.microsoft.com/en-us/sql/relational-databases/tables/specify-computed-columns-in-a-table?view=sql-server-2017 Before You Begin Limitations and Restrictions A computed column cannot be used as a DEFAULT or FOREIGN KEY constraint definition…
