Learn
Functions
Review
Excellent work! 👏 In this lesson, you’ve covered a major fundamental programming concept used in the majority of all programs to organize code into reusable blocks.
Here’s a recap:
- A function definition consists of a function name followed by optional parameters and a return type.
- The function body holds the function’s task.
- A function will execute only when it is called.
- A
return
keyword is used to return a value from a function. - A function’s return type is specified in the function definition followed by an
->
. If a function does not return any values, it’s return type isVoid
or the arrow and type are omitted entirely. - A
return
statement can be omitted if the function consists of only one expression to return. This is called an implicit return. - A parameter is a placeholder for a real value passed into a function. A parameter must be enclosed within
()
of a function definition and must have a specific type. - An argument is a real value passed in for a parameter in the function call.
- A function can accept multiple parameters separated by commas. As many parameters as a function accepts, as many arguments or real values must be passed into the function when it is called.
- A function can return multiple values in the form of a tuple.
- Swift offers support for wide variety of parameter use cases within a function:
- Default Parameter: a parameter that sets a value to the parameter that will be used if an argument is omitted.
- Variadic Parameter: a parameter that accepts zero or more values of the parameter’s type.
- In-out Parameter: a parameter whose value is passed into a function and modified within the body.
Instructions
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