One of the most difficult things about mobile development is asynchronous programming, which means doing different things at the same time. This is not the normal flowchart-style sequence of traditional programming.
Weirdly enough, with Swift completion handlers, an asynchronous function exits before it finishes. Or if you’r not careful, it might never finish at all. 🤯
Oh no! This is entering annoying quantum mechanics territory. 😭
If none of this makes any sense to you, then you’re not alone.
All of this is why I love the following video from WWDC 2021. Nate spends the first eight minutes showing how downloading an image and generating a thumbnail quickly becomes “verbose, complex, and even incorrect” in traditional Swift programming. (Side note: I like how Nate apparently worked hard on his hand gestures as well.)
The payoff: Nate then explains how async/await will let you write asynchronous code basically like “regular code.” 🤩
patmcg.com 
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