# IsClosure

Determine whether a given object is a closure

## Method Signature

```
IsClosure(object=[any])
```

### Arguments

| Argument | Type  | Required | Description                         | Default |
| -------- | ----- | -------- | ----------------------------------- | ------- |
| `object` | `any` | `true`   | The value to test for closure-ness. |         |

## Examples

### Returns true if the object is a closure

[Run Example](https://try.boxlang.io/?code=eJwrLixNLEpVsFXQUHDMq1SoUNBUsLVTqObiLEotKS3KAwpoKVRYc9Vac5UXZZakupTmFmgoZBY75%2BQXlxalaigUQ%2FRrKmhacwEAeU4XPA%3D%3D)

```java
square = ( Any x ) => {
	return x * x;
};
writeDump( isClosure( square ) );

```

Result: TRUE

### Returns false if the object is not a closure

[Run Example](https://try.boxlang.io/?code=eJwrLixNLEpVsFXQUHDMq1SoUNBUsLVTqObiLEotKS3KAwpoKVRYc9VacxWDVaYAlUJYGgqmCprWXOVFmSWpLqW5BRoKmcXOOfnFpSApmGJNkBIA%2BtYerg%3D%3D)

```java
square = ( Any x ) => {
	return x * x;
};
squared = square( 5 );
writeDump( isClosure( squared ) );

```

Result: FALSE

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJxtjkEKAjEQBM%2FOK5o9JSDkASFeFH%2FgA9ZkFgIxK5PMXsS%2FKyoiuMeG6u5yDrHMTYUpIsBYhB1utBHuKhVdlD3dPZFz0MaCxFOunDBpjT3PFeZ0OFr6Rn1O%2FPUp6eVqsIwSctu%2F%2Fwwi7BZlPHMJw0digPXrsP7AqyKv6gNk50I%2B)

```java
// closure
c = () => {
	return true;
};

// user defined function (UDF)
function u() {
	return true;
}
dump( var=isClosure( c ), label="closure" );
dump( var=isClosure( u ), label="user defined function" );

```

## Related

* [ArrayIsEmpty](/boxlang-language/reference/built-in-functions/decision/arrayisempty.md)
* [arrayIsEmpty](https://github.com/ortus-boxlang/boxlang-docs/blob/v1.x/boxlang-language/reference/built-in-functions/decision/arrayIsEmpty.md)
* [Attempt](/boxlang-language/reference/built-in-functions/decision/attempt.md)
* [IsArray](/boxlang-language/reference/built-in-functions/decision/isarray.md)
* [IsBinary](/boxlang-language/reference/built-in-functions/decision/isbinary.md)
* [IsBoolean](/boxlang-language/reference/built-in-functions/decision/isboolean.md)
* [IsCustomFunction](/boxlang-language/reference/built-in-functions/decision/iscustomfunction.md)
* [IsDate](/boxlang-language/reference/built-in-functions/decision/isdate.md)
* [IsDateObject](/boxlang-language/reference/built-in-functions/decision/isdateobject.md)
* [IsDebugMode](/boxlang-language/reference/built-in-functions/decision/isdebugmode.md)
* [IsDefined](/boxlang-language/reference/built-in-functions/decision/isdefined.md)
* [IsEmpty](/boxlang-language/reference/built-in-functions/decision/isempty.md)
* [IsFileObject](/boxlang-language/reference/built-in-functions/decision/isfileobject.md)
* [IsIPv6](/boxlang-language/reference/built-in-functions/decision/isipv6.md)
* [IsJSON](/boxlang-language/reference/built-in-functions/decision/isjson.md)
* [IsLeapYear](/boxlang-language/reference/built-in-functions/decision/isleapyear.md)
* [IsLocalHost](/boxlang-language/reference/built-in-functions/decision/islocalhost.md)
* [IsNull](/boxlang-language/reference/built-in-functions/decision/isnull.md)
* [IsNumeric](/boxlang-language/reference/built-in-functions/decision/isnumeric.md)
* [IsNumericDate](/boxlang-language/reference/built-in-functions/decision/isnumericdate.md)
* [IsObject](/boxlang-language/reference/built-in-functions/decision/isobject.md)
* [IsQuery](/boxlang-language/reference/built-in-functions/decision/isquery.md)
* [IsSimpleValue](/boxlang-language/reference/built-in-functions/decision/issimplevalue.md)
* [IsStruct](/boxlang-language/reference/built-in-functions/decision/isstruct.md)
* [IsValid](/boxlang-language/reference/built-in-functions/decision/isvalid.md)
* [IsXML](/boxlang-language/reference/built-in-functions/decision/isxml.md)
* [IsXmlAttribute](/boxlang-language/reference/built-in-functions/decision/isxmlattribute.md)
* [IsXMLDoc](/boxlang-language/reference/built-in-functions/decision/isxmldoc.md)
* [IsXMLElem](/boxlang-language/reference/built-in-functions/decision/isxmlelem.md)
* [IsXMLNode](/boxlang-language/reference/built-in-functions/decision/isxmlnode.md)
* [IsXMLRoot](/boxlang-language/reference/built-in-functions/decision/isxmlroot.md)
* [LSIsNumeric](/boxlang-language/reference/built-in-functions/decision/lsisnumeric.md)
* [structIsEmpty](/boxlang-language/reference/built-in-functions/decision/structisempty.md)


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