If we try to call a function, such as normal, Swift is going to give us an error, as shown in the following example:
let repeated1 = repeatString("Hello", untilLongerThan: 20)
// Error: Call can throw but is not market with 'try'To eliminate this error, we must add the try keyword before the call. However, before we move forward, I would recommend that you wrap all of your code inside a function, if you are following along in a playground. This is because throwing errors at the root level of a playground will not be handled properly and may even cause the playground to stop working. To wrap your code in a function, you can simply add the following code:
func main() {
// The rest of your playground code
}
main()This defines a function called main that contains all the normal playground code that is called once, at the end of the playground.
Now, let's get back to using the try keyword. There are actually three forms of it: try, try?, and try!. Let's start by discussing the exclamation...