isRichTextValue
function isRichTextValue(value: unknown): value is GoogleAppsScript.Spreadsheet.RichTextValue;
An Apps Script service object has no constructor a script can test against, so the guard reads the tag the object reports for itself: value.toString() === "RichTextValue". A plain object that reports the same tag passes too, which in practice means a test double.
isX and nonX answer a question and never interrupt control flow; requireX and requireNonX hand the value back or throw. The scheme is explained in Validation conventions.
Parameters
Parameter | Type | Description |
|---|---|---|
|
| The value to check. |
Returns
boolean — true when the value is a rich text value; otherwise false.
In TypeScript the guard narrows value to GoogleAppsScript.Spreadsheet.RichTextValue inside the branch.
Examples
What passes and what does not
const value = SpreadsheetApp.newRichTextValue().setText("a").build();
isRichTextValue(value); // => true
isRichTextValue({}); // => false
isRichTextValue(null); // => false
See also
Source
23 September 2026
This documentation was generated with AI (Claude) from the library's source code.