Any way to iterate a tuple in swift?

Solution 1:

Yes, you can!

func iterate<C,R>(t:C, block:(String,Any)->R) {
    let mirror = reflect(t)
    for i in 0..<mirror.count {
        block(mirror[i].0, mirror[i].1.value)
    }
}

And voila!

let tuple = ((false, true), 42, 42.195, "42.195km")
iterate(tuple) { println("\($0) => \($1)") }
iterate(tuple.0){ println("\($0) => \($1)")}
iterate(tuple.0.0) { println("\($0) => \($1)")} // no-op

Note the last one is not a tuple so nothing happens (though it is a 1-tuple or "Single" which content can be accessed .0, reflect(it).count is 0).

What's interesting is that iterate() can iterate even other types of collection.

iterate([0,1])              { println("\($0) => \($1)") }
iterate(["zero":0,"one":1]) { println("\($0) => \($1)") }

And that collection includes class and struct!

struct Point { var x = 0.0, y = 0.0 }
class  Rect  { var tl = Point(), br = Point() }
iterate(Point()) { println("\($0) => \($1)") }
iterate(Rect())  { println("\($0) => \($1)") }

Caveat: the value passed as the 2nd argument of the block is type Any. You have to cast it back to the values with original type.

Solution 2:

You can using reflection Swift 5

Try this in a Playground:

let tuple = (1, 2, "3")
let tupleMirror = Mirror(reflecting: tuple)
let tupleElements = tupleMirror.children.map({ $0.value })
tupleElements

Output:

enter image description here

Any way to iterate a tuple in swift?

Solution 1:

Solution 2:

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