how to capitalize a first letter of each word in array in ES7 or ES8 : how to capitalize a first letter of each word in an array in ES7 or ES8
i tried this, but it didn't work.

    const days = ['sunday', 'monday', 'tuesday', 'wednesday', 'thursday', 'friday', 'saturday'];

days.map(day => day.charAt(0).toUpperCase() + day.substr(1));


console.log(day);

