Methods are a way to encapsulate and provide names for ruby expressions. It helps avoid code duplication, so we can keep calling the same methods when we need them.
There are built-in methods like uncase and downcase. But we can create our own methods too.
def say_hello
puts "Hello, world!"
end
To call the function defined above - say_hello
Hello world!
We can add a parameter “username” to our function
def say_hello(username)
puts "Hello, #{username}!"
end
Let’s call the parametered function with an argument - say_hello("Thanni")
Hello, Thanni!
We can also have a function with multiple parameters.
def say_hello(greeting, username)
puts "#{greeting}, #{username}!"
end
Call the function with arguments- say_hello("Good morning", "Thanni")
Good morning, Thanni!
What if you called a function with one argument, instead of two? That’s why we can assign default values to our parameters.
def say(greeting = "Hello", username)
put "#{greeting}, #{username}"
end
Call the function - say_hello ("Thanni")
Hello, Thanni
The arguments we’ve used so far are positional, i.e they are matched in order defined by the method. To be able to pass arguments in any order, we use keyword arguments.
def example_method(x:, y:)
puts "x: #{x}, y: #{y}"
end
example_method(y: 2, x: 1) # Keyword arguments
Methods return values by default. If the “return” keyword is not explicitly used, the last line in the function block is evaluated.
def some_method
2 + 2
puts "Hello"
5 + 5
end
some_method
10
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