Coding: Working with Data - Typing Practice Lesson
Lists, filter and map, dictionaries, formulas and SQL
Advanced Skills
Focus Keys:
Code
Next: capital D, left middle, right Shift
0
WPM
100%
Accuracy
0
Errors
0%
Progress
Data often comes as a list of objects. In JavaScript: const students = [{ name: "Ava", score: 91 }, { name: "Ben", score: 78 }, { name: "Cy", score: 85 }]; To find everyone who passed, filter the list: const passed = students.filter((s) => s.score >= 80); To get just the names, map it: const names = passed.map((s) => s.name); The result is ["Ava", "Cy"]. Methods like filter and map return new arrays and leave the original list unchanged.
Quick start
- Click the text area above.
- Type the shown text. Prioritize accuracy.
- Use Backspace to correct mistakes.
Tip: Arrows
An arrow like => is the equals key, then Shift plus the period. Practice it until it feels like one motion.