How can I JSON.stringify a Collection in Dart - json

Question

How can I made a JSON string out of a collection in dart, as I can do it with Maps. The docs say I can pass a map or a an array into the JSON.stringify() method. But there are no Array data type in Dart and passing a collection gives me an exception.
I've a naive workaround, but I wonder if there will be a better way to do this:
String s = '[';
bool first=true;
_set.forEach(function(item){
if (first) {
first = false;
} else {
s+=',';
}
s += JSON.stringify(item);
});
s +=']';
print(s);
return s;

Answer 1

In Dart, you can get a JSON String out of an Object using the JsonEncoder's convert method. Here is an example:
import 'dart:convert';
void main() {
final jsonEncoder = JsonEncoder();
final collection1 = List.from([1, 2, 3]);
print(jsonEncoder.convert(collection1)); // prints [1,2,3]
final collection2 = List.from(['foo', 'bar', 'dart']);
print(jsonEncoder.convert(collection2)); // prints ["foo","bar","dart"]
final object = {'a': 1, 'b': 2};
print(jsonEncoder.convert(object)); // prints {"a":1,"b":2}
}

Answer 2

Passing a list works for me:
in the Dart VM importing dart-sdk/lib/frog/server/dart_json.dart
in Dartium importing json:dart
using this code:
void main() {
var list = new List.from(["a","b","c"]);
print(JSON.stringify(list));
}
prints this JSON snippet:
["a","b","c"]
Doesn't work for new Set.from(...) which is expected, given that JSON only deals in maps and lists.