“subscript” used in Swift as an indexer , It is a mechanism to access a chained data such as a custom list by index , here is an example of what we can do with subscript
class Person{
var job:[String]
subscript(index:Int)->(String) {
get{
return self.job[index]
}
set{
self.job[index]=newValue
}
}
func getJob()->String{
return "job"
}
init(profession:[String]){
job = profession
}
}
var jobs=["engineer","physician","shop keeper"]
var p=Person(profession: jobs)
print(p[1])//access mList by index = 1
subscript is particularly useful when dealing with custom list , suppose we keep a person’s Record as:
class Record{
var name:String
var age:Int
init(name:String,age:Int){
self.name = name
self.age = age
}
}
And then we have a list of such a Records as:
class MyList{
var data:[Record]
subscript(index:Int)->Record{
get{
return data[index]
}
set{
data[index] = newValue
}
}
init(list:[Record]){
self.data = list
}
}
let record1 = Record(name: "Smith", age: 23)
let record2 = Record(name: "Bob", age: 46)
let record3 = Record(name: "Kent", age: 66)
let mList = MyList(list: [record1,record2,record3])
let rec = mList[2]//access mList by index = 2
print("\(rec.age)")
