Mikhail, thanks for your feedback! This is a very popular feature. This feature is now available as public preview. Please check out the open spec docs at this location to get more details: https://github.com/OfficeDev/office-js-docs/blob/ExcelJs_OpenSpec/reference/excel/range.md
Additionally, you can try out the new API features by using the built-in code snippets that are available in Script Lab https://github.com/OfficeDev/script-lab/blob/master/README.md. In Script Lab, you’ll find samples that use preview APIs listed in the Preview APIs category:
Please give it a try and let us know what you think.
Office Extensibility Team
185 votesUnder review · 10 comments · Feature Requests and Feedback » Add-in: PowerPoint · Flag idea as inappropriate… · Admin →Mikhail Barycheuski supported this idea ·