常见的Ruby习语

"Hello, World!".upcase

if x > 10
  puts "x is greater than 10"
elsif x > 5
  puts "x is greater than 5"
else
  puts "x is less than or equal to 5"
end

numbers = [1, 2, 3, 4, 5]
sum = numbers.inject(0) { |acc, elem| acc + elem }

numbers = [1, 2, 3, 4, 5]
squared_numbers = numbers.map { |n| n * n }

module Math
  PI = 3.141592653589793

  def self.sqrt(n)
    Math.sqrt(n)
  end
end

class Person
  attr_accessor :name, :age

  def initialize(name, age)
    @name = name
    @age = age
  end

  def to_s
    "#{name}, #{age} years old"
  end
end

begin
  # some code that might raise an exception
rescue StandardError => e
  puts "An error occurred: #{e.message}"
ensure
  # code that will always be executed, regardless of whether an exception was raised
end