tryToSet<T> static method

Set<T>? tryToSet<T>(dynamic object, { dynamic mapKey, int? listIndex, })

Attempts to convert an object to a Set of type T, or returns null if conversion is not possible.

• If the object is already a Set of type T, it is returned as-is.
• If the object is an Iterable, it converts it to a Set of type T.
• If the object is null, returns null.
• If the object cannot be converted to a Set of type T, logs an error and returns null.

object The object to be converted to a Set of type T. mapKey (Optional) Specifies the key to extract values from a Map object. listIndex (Optional) Specifies the index to extract elements from a List object.

Returns a Set of type T if conversion is successful, otherwise null.

Example usage:

final object1 = {1, 2, 3};
final set1 = ConvertObject.tryToSet<int>(object1); // {1, 2, 3}

final object2 = [1, 2, 3];
final set2 = ConvertObject.tryToSet<int>(object2); // {1, 2, 3}

final object3 = 'Hello';
final set3 = ConvertObject.tryToSet<int>(object3); // null (logs an error)

final object4 = null;
final set4 = ConvertObject.tryToSet<int>(object4); // null

Implementation

static Set<T>? tryToSet<T>(
  dynamic object, {
  dynamic mapKey,
  int? listIndex,
}) {
  if (object is String) return tryToSet(object.decode());
  if (object is Iterable && object.isEmpty) return <T>{};
  if (listIndex != null && object is List<dynamic>) {
    return tryToSet<T>(object.of(listIndex));
  }
  if (mapKey != null && object is Map<dynamic, dynamic>) {
    return tryToSet<T>(object[mapKey]);
  }
  if (object is Set<T>?) return object;
  if (object is T) return <T>{object};
  if (object is Map<dynamic, T>) return object.values.toSet();
  try {
    if (mapKey != null && object is Map<dynamic, dynamic>) {
      return tryToSet(object[mapKey]);
    }
    if (object == null) return null;
    return (object as Iterable)
        .map((tmp) => tmp is T ? tmp : toType<T>(tmp))
        .toSet();
  } catch (e, s) {
    log(
      'toSet() Unsupported object type ($T): exception message -> $e',
      stackTrace: s,
      error: e,
    );
    return null;
  }
}