You want to collect the first 3 values from an async sequence updates into an array. Which code correctly does this?

hard📝 Application Q15 of 15

iOS Swift - Concurrency

You want to collect the first 3 values from an async sequence updates into an array. Which code correctly does this?

Avar results = [] for await update in updates { results.append(update) if results.count == 3 { break } }

Bvar results = [] for update in updates { results.append(update) if results.count == 3 { break } }

Cvar results = [] while let update = await updates.next() { results.append(update) if results.count == 3 { break } }

Dvar results = [] updates.forEach { update in results.append(update) if results.count == 3 { break } }

Step-by-Step Solution

Solution:

Step 1: Understand async sequence iteration and breaking
Use 'for await' to iterate async sequences and break when count reaches 3.
Step 2: Evaluate each option
var results = [] for await update in updates { results.append(update) if results.count == 3 { break } } uses 'for await' with break after 3 items, correct. var results = [] for update in updates { results.append(update) if results.count == 3 { break } } lacks 'await'. var results = [] while let update = await updates.next() { results.append(update) if results.count == 3 { break } } uses invalid syntax for async sequences. var results = [] updates.forEach { update in results.append(update) if results.count == 3 { break } } uses 'forEach' which doesn't support async iteration or breaking.
Final Answer:
var results = [] for await update in updates { results.append(update) if results.count == 3 { break } } -> Option A
Quick Check:
Use 'for await' and break after 3 items [OK]

Quick Trick: Use 'for await' and break after collecting 3 items [OK]

Common Mistakes:

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