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JavaScript React by Example Building the Application Writing a Handler to Confirm Guests

Waqar Ashraf
Waqar Ashraf
3,742 Points

returning object

toggleConfirmationat = (indexTochange) => {
        this.setState({
            guests: this.state.guests.map((guest, index) => {
                if (index === indexTochange) {
                    return
                     {
                        ...guest,
                        isConfirmed: !guest.isConfirmed
                    }
                }
            })
        })
    };

Hi i on line 5 if i put curly brace in next line to return i get error and if i put very next to return i do not get error can please any one tell me the reason ?

1 Answer

Jesus Mendoza
Jesus Mendoza
23,273 Points

That's because the JavaScript compiler adds a semi colons after some keywords like return, so in this case when it sees the return keyword and adds a semi colon to the end of it then the function returns without executing the rest of the code and returning undefined.