[swift-evolution] map-like operation that returns a dictionary

[肇鑫]

You can use dictionary in a map. You just ignore the return value of the
map.

var dic = [Int:String]()
var index = 0

["John", "Mike", "Amy", "Kavin"].map {
    dic.updateValue($0, forKey: index)
    index += 1
}

print(dic) // [2: "Amy", 0: "John", 1: "Mike", 3: "Kavin"]

zhaoxin

On Mon, Jan 11, 2016 at 1:50 AM, Kenny Leung via swift-evolution <
swift-evolution at swift.org> wrote:

> Hi All.
>
> I find that instead of using map() on arrays, I more often use an
> operation that returns a dictionary from an array. A common case is
> fetching an array of data, then creating a local cache of it indexed by ID.
>
> Is there a name for this operation? Is this something that others would
> like to see added to the standard library?
>
> -Kenny
>
> _______________________________________________
> swift-evolution mailing list
> swift-evolution at swift.org
> https://lists.swift.org/mailman/listinfo/swift-evolution
>



-- 

Owen Zhao
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