Default and Variadic Parameters
Setting default values and accepting variable numbers of arguments.
Welcome
Default parameter values let callers omit arguments they don't need to customise. Variadic parameters accept any number of arguments. Both reduce boilerplate and improve APIs.
Default Parameter Values
```swift
func log(_ message: String, level: String = "INFO") {
print("[\(level)] \(message)")
}
log("Server started") // [INFO] Server started
log("Disk full", level: "ERROR") // [ERROR] Disk full
```
Defaults must be placed after required parameters.
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