- Comprehensive Ruby Programming
- Jordan Hudgens
- 351字
- 2021-07-02 21:13:30
What does a Ruby method return?
Learning what a method returns is critical in any programming language. Ruby specifically has a unique way of working with returned values. In this section, you are going to learn what a method returns.
I'm going to use the same method we created in the last section, which is as follows:
def baseball_team_list
p ["A's", "Angels", "Astros"]
end
baseball_team_list
In other traditional programming languages, you have to explicitly use the return word to tell the method to return the values you want. For example, you would have to type something like this:
def second_baseball_team_list
return p ["A's", "Angels", "Astros"]
end
second_baseball_team_list
Now, if you hit run, this code will get executed without any errors. However, Ruby does not need an explicit declaration of return like this because it is smart enough to know that it has to return the last line of code inside the method. Also, using the return word is considered a poor practice for the following reasons:
- We want to avoid using extra code when it's not needed.
- It may confuse experienced Ruby developers. The only time you want to use the return word is when you want a method to end prematurely.
You can use the return word as a part of a conditional, so that the method returns one set of values when the condition is met, and another set when it is not met. Consider this example:
def second_baseball_team_list
x = 10
return ["A's", "Angels", "Astros"] if x == 10
["yankees", "Mets"]
end
p second_baseball_team_list
If you run this method, it returned the "A's", "Angels", "Astros" values because the value of x is 10. Also, if you notice, it skipped the second set of teams entirely because when the condition was met, the program simply returns the value and exits. This means that when you have the return word, the remaining part of the method does not get executed. Now, if I change the value of x to 15, then it prints "yankees" and "Mets".
So, this is the one time you can use the return word in Ruby.
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