Functions are useful when writing code because you can reuse code without rewriting it every time you need it. Functions are defined with three components: header, parameters, and body.
- Header – includes the def keyword, the name of the function, and parameters required by the function
- Parameters – also called arguments; what the function needs to do work (i.e. numbers, words, etc.); there can be as many parameters as you need for your function to do the job it is given
- Body – can include comments to help explain what the function is doing; the body is indented, like if/elsif/else-statements
- End – you must include the end keyword to end your function
After defining a function, it must be called to be implemented. If you do not call your function, it cannot do the work it was designed for.
Functions can be useful for simple things such as printing text or completing simple arithmetic problems. They can also be used for much more powerful tasks. For example, a function can call another function and a function can call itself. When a function calls itself, this is called recursion.
| Function calling another function