addtime

Adder of Time https://pistonite.github.io/addtime

To use in Google Sheet Apps Script

In your Google Sheet, go to Extensions > Apps Script, and paste in this script

You will have access to the ADDTIME function which adds a range of cells, and the SUBTIME function that subtracts 2 cells

To consume as TypeScript library

Download the source to your project

curl https://pistonite.github.io/addtime/time.ts > somewhere/addtime.ts 

Then map the path in your tsconfig.json

{
    "compilerOptions": {
        "paths": {
            "addtime": ["base/rel/path/to/somewhere/addtime.ts"]
        }
    },
    "include": ["path/to/somewhere"]
}

Finally import and use

import { calc } from "addtime";