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# isJoinControl

A Boolean value indicating whether the scalar is a format control
character that has a specific function in controlling cursive joining and
ligation.

```
var isJoinControl: Bool { get }
```

## Discussion

There are two scalars for which this property is `true`:

- When U+200C ZERO WIDTH NON-JOINER is inserted between two characters, it
  directs the rendering engine to render them separately/disconnected when
  it might otherwise render them as a ligature. For example, a rendering
  engine might display “fl” in English as a connected glyph; inserting the
  zero width non-joiner would force them to be rendered as disconnected
  glyphs.
- When U+200D ZERO WIDTH JOINER is inserted between two characters, it
  directs the rendering engine to render them as a connected glyph when it
  would otherwise render them independently. The zero width joiner is also
  used to construct complex emoji from sequences of base emoji characters.
  For example, the various “family” emoji are encoded as sequences of man,
  woman, or child emoji that are interleaved with zero width joiners.

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

---

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