TypeScript reporting Object is possibly 'undefined' when it shouldn't

Question

I\'m trying to understand why TypeScript is giving me the following error: Object is possibly \'undefined\'

Here\'s the code snippet:

Answer 1

If you query for a key not in the map, you will get undefined. Not because the map holds an undefined value, but because it does not hold a value at all.

Try

results.get(key)!

Or

results.get(key) as number