A convenience wrapper around assert that returns the value if the assertion passes.
Value to assert present or true. Same rules as assert.
Optional
Optional error message when the assertion fails. Defaults to "Assertion failed".
"Assertion failed"
The asserted value, narrowed to T.
value
T
function findUser(id: number): User | null;const user = ensure(findUser(123), "User is required");// ^? User Copy
function findUser(id: number): User | null;const user = ensure(findUser(123), "User is required");// ^? User
If value is false, null, or undefined.
false
null
undefined
A convenience wrapper around assert that returns the value if the assertion passes.