Defining a method with equals signs in Ruby

I'm trying to crea开发者_Python百科te a User class that would store only hashed password

class User
  # Password should be stored only as hash in @password_hash,
  # crypted by that function:
  def self.crypt(password)
    # Returns password hash
  end

  # Crypt password and store it in @password_hash
  def password=(str)
    @password_hash = crypt(str)
  end

  # Crypt given password and compare it with stored @password_hash
  def password==(str)
    @password_hash == crypt(str)
  end
end

me = User.new
me.password = 'qwerty'

if me.password == 'qwerty'
  puts 'Ok'
else
  puts 'Error'
end

But I get a syntax error, unexpected tEQ, expecting '\n' or ';' on 14 line

You can't define a method called password==. Assignments are special; comparisons are not. If you really want to use User.password == "something" syntax, this is the way to do it:

class User
  attr_reader :password
  def password=(str)
    @password = Password.new(str)
  end

  class Password < String
    def encrypt(str)
      "foo" + str # TODO make stronger
    end

    def initialize(str)
      super(encrypt(str))
    end

    def ==(other)
      super(encrypt(other))
    end
  end
end

Try:

def == str
   @password_hash == crypt(str)
end

Also take a look at the Comparable module.