Catrobat.IDE.Core.Formulas.Editor.FormulaEditor.Delete C# (CSharp) Method

        private bool Delete()
        {
            if (Tokens == null) return false;
            if (SelectionLength > 0)
            {
                var index = SelectionStart;
                if (!(0 <= index && index + SelectionLength <= Tokens.Count)) return false;
                Tokens.RemoveRange(index, SelectionLength);
            }
            else
            {
                var index = CaretIndex - 1;
                if (!(0 <= index && index < Tokens.Count)) return false;
                Tokens.RemoveAt(index);
            }
            RaisePropertyChanged(() => CanDelete);
            return true;
        }