empty
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%% The `empty` value, represented by `_`, is a placeholder indicating absence of a value, missing data, or an intentionally ignored element. It is used to represent missing values in tables and skipped elements in tuple destructuring.
1. Syntax
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An empty value is written using one or more underscores `_`:
```mech:disabled
_
___
```
2. Kind
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The kind of an empty value is just empty:
```mech:disabled
<_>
```