what word? if you mean tracks and prop… prop is a variable used in the code, it is one of the parameters of the updateRecords function. "tracks" is one of the possible values of prop. prop indicate the property name of the object that the function should change
the property tracks is an array, if you need to update the property tracks you need to add a value to the array. If the array doesn’t exist, you can’t add a value to an array that doesn’t exist (you would see error TypeError: Cannot read property 'push' of undefined), so you need to create an empty array before trying to add the value to the array
so i must return value , like first step =>collection[id][prop] = value; but he give me error after create array? like this:
else if(prop === “tracks” && !collection[id][prop] === “tracks”){
collection[id][prop] = ;
collection[id][prop] = value;
now I’m lost , I write this { !collection[id][prop] === “tracks”
} because he said :
but the album doesn’t have a "tracks" property,
he doesn’t say: value === “tracks”;
no, you need to assign an array with the assignment operator (=), remember that an array has the square brackets around it. value is a string, [value] is an array