String & Array Drills
Rapid composition of slice, split, join, map, filter, and find. The methods you reach for every day in real codebases.
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The eight methods you'll use forever
Open any file in the React, Next.js, or VSCode source. You'll see the same handful of methods used over and over: split, join, slice, map, filter, find, some, includes. Master these and you can transform almost any data shape.
This lesson is rapid-fire practice. Each drill is small. Don't overthink — just type.
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