Make an assertion, error will be thrown if expr does not have truthy value.

Make an assertion that actual and expected are equal, deeply. If not deeply equal, then throw.

Make an assertion that obj is an instance of type. If not then throw.

Executes a function which returns a promise, expecting it to reject.

Make an assertion that actual and expected are strictly equal. If not then throw.

Executes a function, expecting it to throw. If it does not, then it throws.

Use this to assert unreachable code.