Intro to Ruby - 05 - Methods

001_ruby_methods.rb

## Basic Method
def say_hello
  puts “Hello”
end

hello # => Hello

## Method with an argument
def say_hello_to(name)
  puts “Hello, #{name}”
end

say_hello_to("Michael") # => Hello, Michael

## Method with an argument with a default value
def hello(name = nil)
  puts “Hello#{(‘,’ + name) if name}”
end

hello # => Hello
hello("Michael") # => Hello, Michael

## Method that explicitly returns a value
def hello(name = “”)
  s = “Hello”
  s += “, #{name}” unless name.empty?
  return s
end

hello # => "Hello"
hello("Michael") # => "Hello, Michael"

## Because this method returns a string, we can use
## the method as the input to the PUTS method, to
## print the result of the method to the screen.

puts hello("Michael") # => Hello, Michael

## Doing the above is the same as doing
puts "Hello, Michael"

002_other_method_examples.rb

## Method takes a number, checks to see if
## it's divisible by 2, returns true if it 
## is and returns false if it is not

def is_divisible_by_2(number)
  if( number % 2 == 0)
    return true
  else
    return false
end

is_divisible_by_2(4) # => true
is_divisible_by_2(5) # => false

## Method takes a number and returns the square
## This method doesn't use the RETURN keyword.
## In Ruby, the last line of a method is the 
## returned value.

def square(number)
  number * number
end

square(8) # => 64