[Solved] Given these async functions:func fetchA() async -> Int { 1 } func fetchB() async -> Int { 2 } func combined() async -> Int { let a = await fetchA() let b = await fetchB() return a + b }How can you... | iOS Swift

iOS Swift - Concurrency

Given these async functions:

func fetchA() async -> Int { 1 }
func fetchB() async -> Int { 2 }

func combined() async -> Int {
  let a = await fetchA()
  let b = await fetchB()
  return a + b
}

How can you optimize combined() to run both fetches concurrently using await?

AUse DispatchQueue to run fetches concurrently

BCall fetchA() and fetchB() without await and add results

CUse async let: <br>async let a = fetchA()<br>async let b = fetchB()<br>return await a + await b

DAwait fetchA() then fetchB() sequentially as is

Step-by-Step Solution

Solution:

Step 1: Understand concurrency with async let
Using async let starts both async calls concurrently.
Step 2: Await both results before returning sum
Awaiting a and b after starting them concurrently improves performance.
Final Answer:
Use async let:
async let a = fetchA()
async let b = fetchB()
return await a + await b -> Option C
Quick Check:
async let runs concurrent awaits [OK]

Quick Trick: Use async let for concurrent awaits [OK]

Common Mistakes:

Awaiting calls sequentially
Not awaiting async let variables
Using DispatchQueue instead of async let

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More iOS Swift Quizzes

Given these async functions:

Step 1: Understand concurrency with async let

Step 2: Await both results before returning sum

Final Answer:

Quick Check:

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