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Method Arguments

Method Arguments

0:00 with Jay McGavren

A parameter is a special variable that you declare at the start of a method. When a method takes parameters, you need to provide argument values when calling that method. Ruby sets each parameter variable with the value in the argument.

  • We still can't specify how many seconds our wait method should pause for.
  • But learning about variables was an important step. Now let's learn about the last piece of the puzzle: method parameters.
  • A parameter is a special variable that you declare at the start of a method.
    • This method takes two parameters, one named first and one named second:
def add(first, second)
  puts first, second
  puts first + second
end
  • When a method takes parameters, you need to provide argument values when calling that method.
    • Ruby sets each parameter variable with the value in the argument.
def add(first, second)
  puts first, second
  puts first + second
end

def subtract(first, second)
  puts first, second
  puts first - second
end

add(100, 50) # 150
subtract(75, 25) # 50
add(3, 4) # 7
subtract(10, 5) # 5
  • Here's our wait method from before, updated with a parameter for the number of seconds it should wait:
def wait(seconds)
  puts "Waiting..."
  sleep seconds
  puts "Done"
end

wait 1
wait 3

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