Variable: FlameGaslets¶

const FlameGaslets: object

Duck-type guards for Google Apps Script Spreadsheet objects.

Uses method existence checks instead of instanceof, which is unreliable across GAS script boundaries and container-bound scripts.

Type Declaration¶

isSheet¶

readonly isSheet: (value) => value is Sheet

Check if a value is a GoogleAppsScript.Spreadsheet.Sheet object.

Parameters¶

value¶

unknown

Value to check

Returns¶

value is Sheet

true if value looks like a Sheet object, false otherwise

Remarks¶

Uses duck-typing to validate Sheet objects by checking for the minimum set of methods: getName, getRange, getLastRow, getLastColumn, getParent. This approach is more reliable than instanceof in Google Apps Script, where objects may not share the same constructor reference across script boundaries.

Example¶

TypeScript

const sheet = SpreadsheetApp.getActiveSheet();
if (FlameGaslets.isSheet(sheet)) {
  const data = sheet.getDataRange().getValues();
}

isSpreadsheet¶

readonly isSpreadsheet: (value) => value is Spreadsheet

Check if a value is a GoogleAppsScript.Spreadsheet.Spreadsheet object.

Parameters¶

value¶

unknown

Value to check

Returns¶

value is Spreadsheet

true if value looks like a Spreadsheet object, false otherwise

Remarks¶

Uses duck-typing to validate Spreadsheet objects by checking for the minimum set of methods: getName, getSheets, getId, getSheetByName. This approach is more reliable than instanceof in Google Apps Script, where objects may not share the same constructor reference across script boundaries.

Note: getUrl is intentionally excluded to avoid false positives with Sheet objects.

Example¶

TypeScript

const book = SpreadsheetApp.getActiveSpreadsheet();
if (FlameGaslets.isSpreadsheet(book)) {
  Logger.log(`${book.getName()} has ${book.getSheets().length} sheets`);
}

Example¶

TypeScript

function processSheet(value: unknown) {
  if (!FlameGaslets.isSheet(value)) {
    throw new Error("Expected a Sheet object");
  }
  const data = value.getDataRange().getValues();
}

See¶

FlameGuards - Guards for primitive and plain JS types

Since¶

0.37.0