Can you explain the significance of using an exclamation mark after defining a variable in TypeScript?

As I delve into TypeScript in an effort to enhance my programming skills, I have encountered the use of exclamation marks when defining variables. An example of this can be seen in the following code snippet:

protected _db!: CheckpointDB

Answer №1

The value is defined, therefore it cannot be null or undefined.

Commonly referred to as: "The non-null assertion operator"

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