# Boolean Toggle with If Node: Empty.List should be the result

**URL:** <https://forum.dynamobim.com/t/boolean-toggle-with-if-node-empty-list-should-be-the-result/39430>\
**Category:** Lists-Logic\
**Created:** [August 13, 2019, 10:06am UTC](https://forum.dynamobim.com/t/boolean-toggle-with-if-node-empty-list-should-be-the-result/39430 "2019-08-13T10:06:59Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Thomas3](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/thomas3/32/102896_2.png) [@Thomas3](https://forum.dynamobim.com/u/Thomas3)\
**Post date:** [August 13, 2019, 10:07am UTC](https://forum.dynamobim.com/t/boolean-toggle-with-if-node-empty-list-should-be-the-result/39430/1 "2019-08-13T10:07:00Z")

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Hi all,  
I use Dynamo 2.0.3 and Revit 2018.3.  
I want to create a boolean switch. If the switch is on true, it should output a List from the output of the node “List.Transpose” with values. If the switch is on false, it should use output an empty list.

The problem is, that if I use List.Empty, and the boolean is on true, the list is not the output

![emptyList%20boolean%20toogle](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/c/3/c3d333daa673bd4ec3ecb050486f90208f94ce56.png)

[001\_ersterVersuch.dyn](https://forum.dynamobim.com/uploads/short-url/vhnxDKC6x54NmckSHKUXZUzF3Ed.dyn) (144.9 KB)

And another question: If I use “null” instead of List.empty, why is Dynamo using the list structure of the true input ?

![null%20boolean%20toogle](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/e/f/efaf20997d676c3e38a596572f0ccf567e6d0878.png)

Thank you,  
Thomas

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<div class="post-metadata">

**Author:** ![Thomas3](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/thomas3/32/102896_2.png) [@Thomas3](https://forum.dynamobim.com/u/Thomas3)\
**Post date:** [August 15, 2019, 10:28am UTC](https://forum.dynamobim.com/t/boolean-toggle-with-if-node-empty-list-should-be-the-result/39430/2 "2019-08-15T10:28:19Z")

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Hi all,[RunMeOrOutputEmptyList.dyf](https://forum.dynamobim.com/uploads/short-url/613VVfws8HmsyJXRLumxwT5FaAz.dyf) (6.7 KB)  
I could solve it by adjusting a node by @Julien_Benoit1  
 ![15-08-_2019_12-26-53](https://us1.discourse-cdn.com/flex022/uploads/dynamobim/original/3X/5/d/5d949618808eeb994f956b8426591180ec34eb49.png)

🙂