Step 6: Custom functionality
In the previous step, we wrote a simple for loop that The name print goes back to when computers used printers, not screens, to interact with their users. some numbers. The name print refers to a “function”, which is a bundle of code. In Ursa, functions are values, and, like other values, we can give them a name. The print function is built into Ursa; but one of the fundamental features of most programming languages is the ability to define new functions.
Defining a new function is exactly what we did in the first part of our program: we defined a function and called it collatz. What does it do?
Let’s look at the ‘outside’ of the function:
fn(n) {…}A function is introduced by the keyword fn, which is followed by two main parts:
- The “parameters”, a list of names in parentheses
- The The same as for a loop., some code in braces which can refer to the parameters
Here, there is just one parameter, n.
The function also “returns” a result. To see what the result, or “return value” might be, we need to look at the body. The return value can be the last value evaluated in the body of the function, or it can be a value of an explicit return expression. Which do we have? In order to answer that question, we will need to examine the function body.