# Learning Angular: Verifying whether a function has been passed to my directive's isolated scope

DevFeed: [Learning Angular: Verifying whether a function has been passed to my directive's isolated scope](<https://devfeed.tech/articles/learning-angular-verifying-whether-a-function-has-been-passed-to-my-directive-s-isolated-scope-21238.md>)

Original publisher: [Read original article](<https://juri.dev/blog/2015/02/learning-ng-verify-presence-of-directive-props/>)

Published: 2015-02-25T00:00:00Z

Content type: tutorial

Language: en

Sources: [Juri Strumpflohner](<https://devfeed.tech/sources/juri-strumpflohner.md>)

Topics: [Angular](<https://devfeed.tech/topics/angular.md>), [modern web development](<https://devfeed.tech/topics/modern-web-development.md>)

Tags: [angular](<https://devfeed.tech/tags/angular.md>), [debug](<https://devfeed.tech/tags/debug.md>), [function](<https://devfeed.tech/tags/function.md>), [optional](<https://devfeed.tech/tags/optional.md>), [parameter](<https://devfeed.tech/tags/parameter.md>), [scope](<https://devfeed.tech/tags/scope.md>), [verify](<https://devfeed.tech/tags/verify.md>)

## AI overview

This Angular tutorial explains why checking whether a function exists on an isolated directive scope can be misleading. It presents inspecting the directive link-function parameters and declaring the function binding as optional so the template can distinguish whether the function was provided.

## Source excerpt

Lorem ipsum dolor sit amet