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# assert

[**utils**](/near-sdk-js/utils.md) • **Docs**

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[near-sdk-js v2.0.0](/near-sdk-js/packages.md) / [utils](/near-sdk-js/utils.md) / assert

## Function: assert()

> **assert**(`expression`, `message`): `asserts expression`

Asserts that the expression passed to the function is truthy, otherwise throws a new Error with the provided message.

### Parameters

• **expression**: `unknown`

The expression to be asserted.

• **message**: `string`

The error message to be printed.

### Returns

`asserts expression`

### Defined in

[packages/near-sdk-js/src/utils.ts:58](https://github.com/near/near-sdk-js/blob/b58ac04fc6dff2f1120e9098c0cb059493486598/packages/near-sdk-js/src/utils.ts#L58)