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# isIDStart

A Boolean value indicating whether the scalar is one which is
recommended to be allowed to appear in a starting position in a
programming language identifier.

```
var isIDStart: Bool { get }
```

## Discussion

Applications that store identifiers in NFKC normalized form should instead
use `isXIDStart` to check whether a scalar is a valid identifier
character.

This property corresponds to the “ID_Start” and the “Other_ID_Start”
properties in the
[Unicode Standard](http://www.unicode.org/versions/latest/).

---

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