Argument Labels and Parameter Names
External vs internal parameter names and how Swift's call-site reads like English.
Welcome
Swift functions have two names for each parameter: an *external* argument label used at the call site, and an *internal* parameter name used inside the function body.
External vs Internal Names
```swift
func greet(person name: String) {
print("Hello, \(name)!")
}
greet(person: "Alice") // call site uses 'person'
// body uses 'name'
```
The external label improves readability at the call site.
All lessons in this course
- Argument Labels and Parameter Names
- Default and Variadic Parameters
- In-Out Parameters and Multiple Returns
- Functions as First-Class Values