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Update name of property initializer proposal #10812

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Sep 26, 2017
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Update name of property initializer proposal #10812

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6 changes: 3 additions & 3 deletions docs/docs/handling-events.md
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Expand Up @@ -97,7 +97,7 @@ You have to be careful about the meaning of `this` in JSX callbacks. In JavaScri

This is not React-specific behavior; it is a part of [how functions work in JavaScript](https://www.smashingmagazine.com/2014/01/understanding-javascript-function-prototype-bind/). Generally, if you refer to a method without `()` after it, such as `onClick={this.handleClick}`, you should bind that method.

If calling `bind` annoys you, there are two ways you can get around this. If you are using the experimental [property initializer syntax](https://babeljs.io/docs/plugins/transform-class-properties/), you can use property initializers to correctly bind callbacks:
If calling `bind` annoys you, there are two ways you can get around this. If you are using the experimental [public class fields syntax](https://babeljs.io/docs/plugins/transform-class-properties/), you can use class fields to correctly bind callbacks:

```js{2-6}
class LoggingButton extends React.Component {
Expand All @@ -119,7 +119,7 @@ class LoggingButton extends React.Component {

This syntax is enabled by default in [Create React App](https://github.com/facebookincubator/create-react-app).

If you aren't using property initializer syntax, you can use an [arrow function](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Functions/Arrow_functions) in the callback:
If you aren't using class fields syntax, you can use an [arrow function](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Functions/Arrow_functions) in the callback:

```js{7-9}
class LoggingButton extends React.Component {
Expand All @@ -138,4 +138,4 @@ class LoggingButton extends React.Component {
}
```

The problem with this syntax is that a different callback is created each time the `LoggingButton` renders. In most cases, this is fine. However, if this callback is passed as a prop to lower components, those components might do an extra re-rendering. We generally recommend binding in the constructor or using the property initializer syntax, to avoid this sort of performance problem.
The problem with this syntax is that a different callback is created each time the `LoggingButton` renders. In most cases, this is fine. However, if this callback is passed as a prop to lower components, those components might do an extra re-rendering. We generally recommend binding in the constructor or using the class fields syntax, to avoid this sort of performance problem.