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JavaScript React by Example Building the Application Building the GuestList Component

TypeError: Cannot read property 'map' of undefined

How can I fix this? import React from 'react'; import PropTypes from 'prop-types';

const GuestList = props => <ul> {props.guests.map((guest, index) => <li key={index}> <span>{guest.name}</span> <label> <input type="checkbox" checked={guest.isConfirmed} /> Confirmed </label> <button>edit</button> <button>remove</button> </li> )} </ul>;

GuestList.propTypes = { guests: PropTypes.array.isRequired }

export default GuestList;

1 Answer

Brendan Whiting
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Brendan Whiting
Front End Web Development Techdegree Graduate 84,677 Points

I can't say for sure without looking at more of the code, but you're probably not passing in the guest prop. You're trying to call .map() here: props.guests.map and it's saying there is no .map() function on guest because guest is undefined.