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Samantha McElhinney1,931 Points
I'm not sure why I'm getting the error identifier already defined when I'm reassigning the variable with const
const century20 = years.filter(number => number <= 2000);
const years = [1989, 2015, 2000, 1999, 2013, 1973, 2012]; let century20; // century20 should be: [1989, 2000, 1999, 1973] // Write your code below const century20 = years.filter(number => number <= 2000);
I don't think you can change between
const within the same scope of a program.
century20 was initialized (with "no value", which I believe evaluates to
null by default) above your code. You no longer need to use the
const keywords on that variable name, or identifier, within this program scope.
It may be clearer to you if it was declared with an initial value, such as
let century20 =  to help mentally track that the variable already exists.