Haxe iteration on Dynamic

Question

I have a variable of type Dynamic and I know for sure one of its fields, lets call it a, actually is an array. But when I'm writing

var d : Dynamic = getDynamic();
for (t in d.a) {
}

I get a compilation error on line two:

You can't iterate on a Dynamic value, please specify Iterator or Iterable

How can I make this compilable?

Answer 1

Haxe can't iterate over Dynamic variables (as the compiler says).

You can make it work in several ways, where this one is probably easiest (depending on your situation):

var d : {a:Array<Dynamic>} = getDynamic();
for (t in d.a) { ... }

You could also change Dynamic to the type of the contents of the array.

Answer 2

Another way to do the same is to use an extra temp variable and explicit typing:

var d = getDynamic();
var a: Array<Dynamic> = d.a;
for (t in a) { ... }