> For the complete documentation index, see [llms.txt](https://docs.documint.me/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.documint.me/templates/working-with-dynamic-data/functions-and-operators/operators/identity-operators.md).

# Identity Operators

### isNull

`{{$isNull value}}`

Evaluates to `true` if `value` is null.

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>value</td><td>A static value or a variable path</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isNull category) }}Category is null{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "category": null
}
```

{% endtab %}

{% tab title="Result" %}
Category is null
{% endtab %}
{% endtabs %}

### isNotNull&#x20;

`{{$isNotNull value}}`

Evaluates to `true` if `value` **is not null**.

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>value</td><td>A static value or a variable path</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isNotNull category) }}Category is not null{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "category": "sports"
}
```

{% endtab %}

{% tab title="Result" %}
Category is
{% endtab %}
{% endtabs %}

### isNil

`{{$isNil value}}`

Evaluates to `true` if `value` is `null` or `undefined` .

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>value</td><td>A static value or a variable path</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isNil category) }}Category is nil{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "category":null
}
```

{% endtab %}

{% tab title="Result" %}
Category is nil
{% endtab %}
{% endtabs %}

### isNotNil&#x20;

`{{$isNotNil value}}`

Evaluates to `true` if `value` is not `null` or `undefined`.

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>value</td><td>A static value or a variable path</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isNotNil category) }}Category is not nil{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "category":"sports"
}
```

{% endtab %}

{% tab title="Result" %}
Category is not nil
{% endtab %}
{% endtabs %}

### isEmpty

`{{$isEmpty path}}`

Evaluates to `true` if the value of the variable `path` *is* `undefined`, `null` , an empty string (`''`) , empty object (`{}`),  or an empty array (`[]`).

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>path</td><td>A path to a variable to check for a value</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isEmpty category )}}Category is empty{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "name":"soccer"
}
```

{% endtab %}

{% tab title="Result" %}
Category is empty
{% endtab %}
{% endtabs %}

### isNotEmpty

`{{$isNotEmpty value}}`

Evaluates to `true` if `value` *is not* `undefined`, `null`, an empty string (`''`),  an empty object (`{}`), and not an empty array (`[]`).

**Arguments**

<table><thead><tr><th width="150">Name</th><th width="272.5333333333333">Description</th><th width="150">Type<select multiple><option value="b0403385da1b4af9a8a894cb7cfa1e88" label="String" color="blue"></option><option value="6a3ca9c830be4cd5a2bcf10d17c44f82" label="Number" color="blue"></option><option value="011b91dfe58a400894b04549ec4f9e02" label="Boolean" color="blue"></option><option value="3c1342f6b38a46e39064bd88015df50d" label="Any" color="blue"></option><option value="331ed19046194ceda3a4dc3fc0789b8f" label="" color="blue"></option></select></th><th data-type="checkbox">Required</th></tr></thead><tbody><tr><td>path</td><td>A path to a variable to check for a value</td><td><span data-option="3c1342f6b38a46e39064bd88015df50d">Any</span></td><td>true</td></tr></tbody></table>

**Returns**

&#x20; *(*[*Boolean*](/legacy-documentation/data-and-variables/data-types.md#booleans)*)*

**Example**

{% tabs %}
{% tab title="Template" %}
{{#if ($isNotEmpty category) }}Category is not empty{{/if}}
{% endtab %}

{% tab title="Data" %}

```json
{
    "category":"sports"
}
```

{% endtab %}

{% tab title="Result" %}
Category is not empty
{% endtab %}
{% endtabs %}


---

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