跪求大侠这个箭头函数里的参数如何解释？

Question

import React from 'react';

import { StyleSheet, Text } from 'react-native';

/**

 * Used across examples as a screen placeholder.

 */

import type { Children } from 'react';

const SampleText = ({children}: { children?: Children }) => (

  <Text style={styles.sampleText}>ww{children}</Text>

);

export default SampleText;

const styles = StyleSheet.create({

  sampleText: {

    margin: 14,

  },

});

({children}: { children?: Children })

括号里的是啥意思？感觉不像三目运算符，谢谢！

Answer 1

这是flow的语法，表示children是Children类型的可选属性详见Interface Properties