/// <summary>
 /// Initializes a new instance of the <see cref="ExpressionObserver"/> class.
 /// </summary>
 /// <param name="inner">The <see cref="ExpressionObserver"/>.</param>
 /// <param name="targetType">The type to convert the value to.</param>
 public ExpressionSubject(ExpressionObserver inner, Type targetType)
     : this(inner, targetType, DefaultValueConverter.Instance)
 {
 }
 /// <summary>
 /// Initializes a new instance of the <see cref="ExpressionObserver"/> class.
 /// </summary>
 /// <param name="inner">The <see cref="ExpressionObserver"/>.</param>
 /// <param name="targetType">The type to convert the value to.</param>
 public BindingExpression(ExpressionObserver inner, Type targetType)
     : this(inner, targetType, DefaultValueConverter.Instance)
 {
 }