29 lines
1.1 KiB
Markdown
29 lines
1.1 KiB
Markdown
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#Nulls unit
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| **Note** |
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| :----------------------------------------------------------- |
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| For versions 2019/2020 LTS, download the visual scripting solution from the [Unity Asset Store](https://assetstore.unity.com/packages/tools/visual-bolt-163802). |
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Null units deal with the null value, which is scripting lingo for "nothing".
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###The null unit
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The null unit always returns null as a value. Leaving a Unity object reference field empty ("None") automatically means null.
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###Null Check
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The null check is a shortcut for a branch on an equality comparison with null. It can be useful to direct the flow in different directions depending on whether a value is null.
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For example, it can be used to handle a situation differently whether a transform has a parent in the hierarchy or not.
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![](images/bolt-nulls1.png)
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###Null Coalesce
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The null coalesce unit provides a fallback value in case the original input is null.
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For example, the null coalesce unit defines a default fallback audio clip in case the one on the audio source is missing.
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![](images/bolts-nulls2.png)
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