> For the complete documentation index, see [llms.txt](https://waoo-app-builder.gitbook.io/waoo-app-builder/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://waoo-app-builder.gitbook.io/waoo-app-builder/nodes/logical-nodes/negation-expr.md).

# Negation - !expr

Logical nodes

| Condition            | Value                                                              |
| -------------------- | ------------------------------------------------------------------ |
| Released in version: | 1.0.14                                                             |
| Flutter/Dart link:   | <https://dart.dev/guides/language/language-tour#logical-operators> |

<figure><img src="https://3643579705-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzuDhZpUY3uOO3NssfE1O%2Fuploads%2FeDV6YXYOW20MyQHJCHJY%2FNegation.png?alt=media&amp;token=f30cf505-1981-45d3-adbf-ac00d53394e6" alt=""><figcaption><p>Negation - !expr default node</p></figcaption></figure>

The "Negation - !expr" node is a logical node used to negate (or invert) the value of a boolean. Therefore if the current value is true, the result is false, and if the value is false, the result is true.&#x20;

Check the table below with the results of this node:

| Item1 | Result |
| :---: | :----: |
| False |  True  |
|  True |  False |

#### Inputs

<table><thead><tr><th>Input Name</th><th width="150" data-type="checkbox">Canvas Required</th><th width="150">Type</th><th>Description</th></tr></thead><tbody><tr><td>value</td><td>true</td><td>Bool</td><td>Value to apply negation</td></tr></tbody></table>

#### Outputs

<table><thead><tr><th width="208.57142857142856">Output Name</th><th width="150" data-type="checkbox">Canvas Required</th><th width="150">Type</th><th>Description</th></tr></thead><tbody><tr><td>result</td><td>true</td><td>Bool</td><td>Result from applying the negation operator to "value" input</td></tr></tbody></table>