config.dart

class Config {
  /// The singleton instance.
  static final Config instance = Config();

  /// All of the configuration items.
  final Map<String, dynamic> _items = <String, dynamic>{};

  /// Get the specified configuration value.
  dynamic get(String key) {
    return _items[key];
  }

  /// Set a given configuration value.
  void set(String key, dynamic value) {
    _items[key] = value;
  }

  /// Determine if the given configuration value exists.
  bool has(String key) {
    return _items.containsKey(key);
  }
}