enum EnumType {
case WithString(String)
}
var enums = [EnumType]()
enums.append(EnumType.WithString("A"))
enums.append(EnumType.WithString("B"))
enums.append(EnumType.WithString("C"))
enums.append(EnumType.WithString("D"))
enums.append(EnumType.WithString("E"))
enums.append(EnumType.WithString("F"))
How to filter my enums
array to find the one with associated value equal C
. What predicate do I need to use?
The filter function can either be invoked as a global function over an array, or as an instance method (I prefer the later as it is more OO).
It accepts a closure with one parameter (the element being evaluated) that return a boolean (indicating whether the element matches the required condition).
Since it's a simple closure in a clear situation it's ok to use the abbreviated form.
I guess that other "With" cases would be added to your enum, so you could go with something like:
let filteredArray = enums.filter {
switch $0 {
case .withString(let value):
return value == "C"
default:
return false
}
}
That should do the trick in your example.