You declare an optional by appending a ? at the end of the data type declaration.

Optionals - If you're familiar with TypeScript, these are very similar to nullable values. Small subtlety here in that it can be initialized without an initial value, and eventually set later, but still may only be set once. Once it's declared, it cannot be mutated. Var - similar to the var and let keyword in JS. In this introduction to Swift, I'll explore different concepts and try explaining how they relate to their counterparts (if one exists) in JavaScript. Swift is the official language created by Apple to develop applications for iOS, macOS, watchOS and tvOS. In order to kickstart this journey into mobile development, I began in the most obvious starting place, learning Swift. There are solutions to mobile development in the JavaScript ecosystem (like React Native) that helped bridge that gap a bit, but I still felt this desire to really understand what was happening behind the curtain.

I was used to this world where JavaScript was the hammer that solved all problems when it came to web development. If you're like me, mobile development can seem intimidating.

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