London | 26-ITP-May | Martin Mwaka | Sprint 2 | Exercises#1252
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Good start, I have a few comments
| function createLookup() { | ||
| // implementation here | ||
| function createLookup(data) { | ||
| validateData(data); |
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Good work on this extensive input validation
| } | ||
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| return array.reduce((acc, item) => { | ||
| acc[item] = (acc[item] ?? 0) + 1; |
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Can you explain how ?? works here?
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This is the nullish coalescing operator. If the acc[item] is undefined it will set it to zero
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Good answer! This task is complete now
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Sprint 2 exercises for module data groups