modeling-app/docs/kcl/assertLessThan.md

---
title: "assertLessThan"
excerpt: "Check that a numerical value is less than to another at runtime,"
layout: manual
---

Check that a numerical value is less than to another at runtime,

otherwise raise an error.

```js
assertLessThan(left: number, right: number, message: string) -> ()
```


### Arguments

| Name | Type | Description | Required |
|----------|------|-------------|----------|
| `left` | `number` |  | Yes |
| `right` | `number` |  | Yes |
| `message` | `string` |  | Yes |

### Returns

`()` 


### Examples

```js
assertLessThan(1, 2, "1 is less than 2")
```

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