# TLO:Defined

## Description

Determines whether a variable, array, or timer with this name exists. The variable, array or timer must not be enclosed with ${}.

## Forms

* [*bool*](/macroquest/data-types-and-top-level-objects/data-types/datatype-bool.md) **Defined\[name]**

## Access to Types

* [*bool*](/macroquest/data-types-and-top-level-objects/data-types/datatype-bool.md) **bool**

## Examples

`/if (${Defined[varname]}) {`\
`/echo ${varname}`\
`}`

## See Also

* [Top-Level Objects](/macroquest/data-types-and-top-level-objects/top-level-objects.md)
* [bool](/macroquest/data-types-and-top-level-objects/data-types/datatype-bool.md)


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