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JavaScript JavaScript Array Iteration Methods Array Manipulation Remove Array Items with filter()

Posted by Tom McLean
Tom McLean
11,045 Points

Why use let for sNames?

Why was sNames declared using let instead of const before changing it to filter? The variable is not reassigned when using Array.push, right?

2 Answers

Doron Geyer
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Doron Geyer
Full Stack JavaScript Techdegree Student 13,897 Points
Doron Geyer
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Doron Geyer
Full Stack JavaScript Techdegree Student 13,897 Points

Hey Tom McLean surprised you never got a response. You were indeed correct. For anyone else who has this same question, const would have been preferable here. He originally used let because he wanted to change the array. Later in the same course he updates it to const when he changes from forEach to filter.

Nils Kriedner
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Nils Kriedner
Full Stack JavaScript Techdegree Graduate 30,933 Points
Nils Kriedner
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Nils Kriedner
Full Stack JavaScript Techdegree Graduate 30,933 Points

I just had the same comment in mind when watching the video...

The convention is to declare arrays with 'const'.

By by changing the content of an array (for example using push()) the array itself is not reassigned. So there is no need to use 'let' here.