assertNotNull - API reference

API reference › @evolu/common › Assert › assertNotNull

const assertNotNull: <T>(
  value: T,
  message?: string,
) => asserts value is T & ({} | undefined);

Defined in: packages/common/src/Assert.ts:762

Asserts that a value is not null while preserving undefined.

Example

import {
  assertEqual,
  assertErr,
  assertInstanceOf,
  assertNotNull,
  assertType,
  trySync,
} from "@evolu/common";

const value = undefined as string | null | undefined;
assertNotNull(value);

assertType<typeof value, string | undefined>();
assertEqual(value, undefined);

const result = trySync(() => assertNotNull(null));
assertErr(result);
assertInstanceOf(result.error, Error);
assertEqual(result.error.message, "Expected value not to be null.");