# `ExternalItemFunctionCallback(data, callback)`

<!-- YAML
title: "Type Alias: ExternalItemFunctionCallback"
source_link: lib/ExternalModuleFactoryPlugin.js#L48
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- `data` {ExternalItemFunctionData}
- `callback` {(err?: null | Error, result?: string | boolean | string[] | ExternalItemValueObjectKnown & ExternalItemValueObjectUnknown) => void}