Asserts given conditions.

(
  condition: boolean,
  callbackOrMessage:
    | {
        (): void;
      }
    | string
) => void

assert(true === false);
// ⇒ TypeError("Assertion failed!")

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Computes a deep difference between the two values (primitives, objects, arrays, etc.).

(
  obj1?: {
    [index: string]: any;
  },
  obj2?: {
    [index: string]: any;
  }
) => object

diff({ a: 1 }, { a: 2 });
// ⇒ { a: { data: [1, 2], type: '~' }}

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